As I said, I haven't had the bet. I just thought it was interesting. I'm going to play a bit of devils advocate here billy, as of course, as you rightly pointed out ... it is all about opinions
I think it is harsh to say "he simply isn't" and needs to prove it. Ratings are given 'officially' by a fella, with an opinion and a set of rules that are not (and can't be scientific). Best system we have of course, but ultimately, you can't define who is the best or who has proven or achieved what.
You can say he isn't rated as highly as other horses, which is true, but Phil Smith has said himself that he COULDN'T give the horse a higher rating than Coneygree's GC yet... but he only CAN'T because of his own set of rules. He "hasn't been given the chance" which is a quote from Phil Smith on meet the handicapper after the King George on ATR.
I'd also dispute Thistlecrack being the worst price of the festival. He won the King George, eased down. That is a pretty good barometer of his ability and we know his target. ANY horse could get injured, fall or unseat, (including the horses behind hm in the market, DC,NR,Djak etc) The chance of injury and not turning up could be applied to every horse so really we shouldn't bet on any horse ante post. I don't think Don Cossack at 10 or 12 is a better bet than Thistlecrack at even at this stage. He hasn't had a run since, might not be as good as he was, and
even if he was that might not be good enough... looking at Cue Card last year I would say he has very closely tied level of form with DC, and on this years form Thistlecrack is a good deal better than CC.
Could flip it on its head too and say evens might look amazing if DC doesn't turn up, NR gets injured, Djakadam goes for the Ryanair and so on.
Also, when he was jumping those open ditches, my heart was in my mouth, and if I didn't get that thrill, and didn't seek it, then I would feel I am missing the point of national hunt racing? This might divide opinion too, but I'd sooner back Thistlecrack at even than Douvan at 1/3. I'd say Douvan is a worse bet, at this stage, than Thistlecrack is.