With regards to class dropping, in Canny Danny's case he had dropped in class from a 2nd as 13/2 4th in the betting to Burrough Hill Lad (fav) to the SGB Chase at Ascot carrying more weight as would nearly always be the case. He beat Fortinas Express at Ascot who had been 4th in the same higher class race as Canny Danny LTO and had won his 3 previous races. FE was 5th in the betting at 10/1 rec 8 lb from CD.
But Canny Danny was taking a class of race drop at Sandown and no other horse in that Sandown event was dropping in class other than the outside Little Polvier who'd finished 11th of 18 in the Welsh National class 191.
And the opposition in the SGB, in the finish or as a field were better than the Sandown race.
The paragraph you refer to in Betting The VDW Way, to my mind at least, is talking about the class of race in which a horse competes being different to the class of horses engaged in that race. In his later return article to Roushayd he made an important extra point about Shimshek and Ala Hanouk "not having much in the way of class (AS HORSES)" which seemed a clear reference to me that the much higher class of races they had been running in were very different to their ability ratings.
And his view on that seems to be confirmed in the very first example Prominent King. PK's last race was a very low class handicap in monetary terms, but the horse he tried to give so much weight to was dropping from a 3rd (at big odds and not first 3 of the betting) in a much higher class race in money terms than even the Erin never mind the paltry 600 quid on offer for Tick Nock Handicap.
Beacon Light's opposition/key horses had been better (on VDW's class ratings) in the higher class races he had run in before Sandown's Oteley Hurdle than Sea Pigeon, which compounded the issue. BL had been dropped to collect again but was beaten by a horse coming from a lower class win (lower class than others BL had beaten recently) and with a lower ability rating than BL.
Also interesting the the weights in the SGB were also raised overnight to the tune of 15 lb so CD would have carried 10-7 in that race also but for them going up. It didn't hinder him in victory though of course weights only go up because horse rated much higher on the handicap came out. And that lessens the strength of opposition to various degrees depending on the form and class of those withdrawn. Which is probably why VDW said he only bought the SCHB for the weekly publication of the framed weights (his words
Chesham ) so that he could study well in advance as well as work out the top, middle and bottom of the framed weights NOT the weights after final decs.Of course as you say
JennyK we could just be chasing our tails. VDW always presented things in a positive light and chose to use days where the more obvious numerical pictures were shown. Early on he said Love From Verona was the only good thing (though those wanting more bets could have backed Gaffer on the same card too). But if he'd show LFV in the same way he did with Diamond's Edge or Little Owl, etc readers would rightly have been saying "Hang on a minute Mr Van Der Wheil. How can the horse with the second lowest ability rating in the race be "good thing?".Just a point on your on going consistent form studies. Pegwell Bay still throws up a consistent form horse who was higher on ability rating, but was not classed as the class/form horse by VDW in Jim Thorpe. We know why he discarded him, but it wasn't for being inconsistent or out of form. It was distance and going at this level.
Which led me to an observation that may have some relevance in the context of Canny Danny being a class/form horse. Canny Danny had just recently won a race of class above his AR of 76. The Sandown race was class 103 and lower than the race CD won.
Jim Thorpe had also won a race of class above his AR of 52 in class 97. But the Mackeson was class 221.
So the comments VDW made about JT was given in the context of "At this level, has no chance."
I've added it to the archive: 
