The Greasy Poll is written in diary form and takes us through the two and a bit years Mike spent campaigning to win the Westminster seat for Plaid. He lost, of course, but that was not for want of trying, and we follow the journey of a political innocent who is slowly and remorselessly put through the political wringer and then spat out on the other side.
The campaign came at enormous personal, emotional and financial cost to Mike. Ceredigion is the complete antithesis of the vast swathes of safe Tory and Labour seats which the first-past-the-post system produces. There the biggest and only real battle most would-be MPs face is manoeuvring through the party machinery to get their names on the ballot paper, which for most of them then becomes a meal ticket for life.
In Ceredigion and other constituencies outside the Labour and Tory heartlands you have to fight every inch of the way and sacrifice a year or two of your life, surviving on your life savings and fresh air. You will have to learn to fight on several fronts, learning to cope with your own party machinery which will set out to emasculate you and turn you into an on-message automaton. You will have to learn to deal with your political rivals, the voters themselves and the media.
It was Mike's misfortune to fight a patch where the only media show in town was the Cambrian News, by some margin the nastiest and most dishonest local newspaper in this part of the world.
Regular readers of this blog will be familiar with quite a few of the characters who have walk-on parts in the book. There goes Gethin James, Aberporth's UKIP councillor, dragging his knuckles along the ground. There goes Henrietta Hensher, the Tory candidate who shows what she thinks of voters by failing to turn up to most of the hustings. There goes Labour careerist, the slick and very ambitious Huw Thomas who will forever be associated with Tippex. There goes Mark Williams, the LibDem MP.
Williams is probably the most interesting character in the book. In many of his press photos he is a startling and deathly shade of white, with a chameleon-like knack of passing himself off as whatever you want him to be. The LibDem self-proclaimed rebel MP who voted with the Tories 97% of the time between 2010 and 2015. A man who can vote for, against and abstain on the bedroom tax: truly a politician for all seasons.
What emerges from the book is a man who keeps his hands as white as the rest of his ghostly complexion, leaving the dirty tricks to his camp followers, such as the disturbed and rather creepy figure of "Joe" and the bad tempered and graceless Elizabeth "I may vomit on you" Evans.
But this book is by no means a one-sided rant. There are some candid portraits and cameos of a number of Plaid politicians past and present, including the ever-green Cynog Dafis who is a fan of fracking and would like to see wind turbines all over the slopes of Pumlumon. Elin Jones features prominently, as you would expect in a Ceredigion election. Elin knows her constituency like the back of her hand; she is tough and yet surprisingly weak when it comes to dealing with the Cambrian News.
Mike is an old and close friend of Leanne Wood, and yet he is surprisingly kind to her nemesis, the baroque loose cannon that is Dafydd Êl (Dafydd Elis Thomas).
In a review in Golwg, Ifan Morgan Jones described the book as being a bit like the maiden voyage of the Titanic. We all know what happens at the end, but the interesting stuff is the journey up to the iceberg.
Perhaps, but Mike's account of the meltdown that followed the Cambrian News "Nazigate" episode does not disappoint. With just two weeks to go before polling day, the newspaper smeared him in what looked for all the world like an attempt to throw the election. The actions of the editor, Beverly Thomas, and the paper's politics reporter, Chris Betteley, could and should have been pursued through IPSO and the courts.
Despite that, Mike thinks that there were other factors at play which cost him the election, chief of which were middle-England fears, stoked by the Tory media, of a Labour government beholden to the SNP.
Mike's most depressing message last Tuesday was that playing the race card always wins in politics, and that one of the biggest changes he has seen in the last 30 years is that it has now become acceptable once again to air prejudices and hatreds of "them" - "them" being minorities and anyone who is palpably not one of "us".
Mike gives us several examples of what he and fellow canvassers encountered on doorsteps. In Aberporth, a Londoner talks of being "forced out" of the city by "them". He escaped to the country to live in Noethamptonshire, only to find that "they" were turning up in droves there too. So he and the missus decided to come to Wales.
Then there is the woman who refuses to accept a leaflet because it is written in English and Welsh, and she does not want "that language" touching her skin. Cymraeg can be very infectious.
While Mike was meeting these charmers in Ceredigion, things were not always much better on the other bank of the Teifi.
Just down the road from Y Cneifiwr live Mr and Mrs M, also blow-ins from London. Mrs M has strong views about "them" and the Welsh. The Welsh are dirty, she says, and they stick together like a gang of thieves. Mr M briefly took on a job as a driver after they settled here, but gave that up because he could not get on with all those stupid place names.
Not that Mr M needed the work because the couple are very well off.
Now this lovely couple are both retired, and they drive off most mornings in their shiny monster £30,000 estate with their snarly Shih tzus to exercise in "Senaaff", or as the road signs stubbornly have it, "Cenarth".
Come election time, a Plaid canvasser called round, only to be sent away with a flea in his ear. "We won't be voting for you because you are a bunch of racists", bellowed Mr M.
Mrs M later told Mrs Cneifiwr that they had voted Tory because the Tories looked after pensioners, and she had stuffed quite a bit of money into George Osborne's "granny bonds".
People like that are nothing new, but perhaps Mike Parker is right. Whereas they used to keep their nasty prejudices behind the net curtains, we now live in a Britain where it is OK to bellow them at anyone who will listen.
On Radio 4's Today Programme earlier this week, the BBC was down in Dover talking to workers in a factory owned by an Italian which depends for its existence on trade with the EU. The factory, which makes gift boxes for champagne and other luxury goods, employs seasonal workers in the summer, including Poles and Latvians.
The Poles and Latvians were decent people, said one local worker, but she would be voting "Leave", presumably dimly aware that Brexit would most likely put her employer out of business, not because of them, but because of "them", the others.
"Them" being that nebulous swarm of foreigners, and foreigners as we know from the Daily Mail, Daily Telegraph, Express, Star and the rest are rapists, criminals and benefit scroungers who come here to take away jobs from ordinary people, wiping bottoms in old people's homes, picking fruit, cleaning and staffing the NHS. The bastards.
These images and all those EU myths have been the staple fare of most of our newspapers for decades, but what has changed is that they have now been joined by Farage and his little helpers fanning the flames, a veneer of respectability being given to the enterprise by the likes of Boris Johnson and even Gisela Stuart (Labour).
Whereas Enoch Powell became political poison after his rivers of blood speech, Boris Johnson's career has gone from strength to strength since he talked about "picaninnies and their watermelon smiles", and Farage can talk repeatedly about violence and warn of foreign rapists. Even Gisela Stuart, who should know better, can get away with claiming on the BBC that the EU is forcing the NHS to employ doctors who can't speak English.
No it isn't. If the NHS employs people who cannot communicate adequately in English, that is down to poor recruitment practices by the NHS. Try getting a job as a doctor in Germany without being able to speak German, and see how far you get.
Any lingering doubts as to whether it is socially acceptable to mouth off like this can be set aside because even the Royals are at it. The Duke of Edinburgh has been doing it for years, of course, as he travels the world talking about "slitty eyes" and the rest, but even the Queen, gawd bless her, has had her moments.
In the grovelathon of the 90th birthday celebrations, BBC viewers were treated to a hilarious anecdote by the actor Sir David Jason. Her Majesty had once met a black African ambassador and nearly mistaken him for a gorilla. How the studio guests and presenter laughed at that example of the monarch's legendary wit, except for will.i.am, the black American singer who looked very uncomfortable.
All very unfortunate, and the press were quick to rally round to explain that Jason had got it wrong. Mrs W had in fact been referring to the ambassador's body proportions. So that was all right. For one terrible moment we had all been left thinking that the Queen thought a black man looked like a gorilla, whereas she had merely thought that he looked like a gorilla.
The Grosvenor meeting was on Tuesday evening, and I was still thinking about the book and its message on Thursday on the drive back, via Cardigan, from Fishguard. In all of those 30 miles, there was not a single Leave or Remain poster or billboard to be seen.
Everyone is as fed up with this sickening, hate-filled referendum campaign as I am, I thought, as someone who normally enjoys politics and campaigning.
And then the news came through on the car radio of the brutal murder of Jo Cox MP.
Let's give the last word to Alex Massie writing for The Spectator:
When you encourage rage you cannot then feign surprise when people become enraged. You cannot turn around and say, ‘Mate, you weren’t supposed to take it so seriously. It’s just a game, just a ploy, a strategy for winning votes.’
When you shout BREAKING POINT over and over again, you don’t get to be surprised when someone breaks. When you present politics as a matter of life and death, as a question of national survival, don’t be surprised if someone takes you at your word. You didn’t make them do it, no, but you didn’t do much to stop it either.