I was amazed by the performance, moreso by the fact that good and all that it was, there was room for improvement.
Turning for home, it looked as if Thistlecrack was still gassy - running with the choke out - and a horse as good as Cue Card (another gassy traveller at times) under pressure. My initial impression was Scudamore slowing down into the last cost him 3l or so, but beginning to think that Thistlecrack may have got as far as he could while still barely under control. He didnt finish the race in the same way he was doing so over hurdles last year.
I find it hard to see what horse is talented enough to be near him when he runs out of gas, but if running the same way, it could happen up the hill at Cheltenham. And 5/4 is tight on that basis. I would suspect that if Jenny Pitman trained the second favourite, what tactic could be employed to keep him lit up but if he could ever be switched off i would think he has another 10l on this week's performance. if zipping around Kempton for the next four years is all he does, that would keep me happy.
Your post, especially the part where you say he was slowing down,got me thinking so I took a closer look at the race.
I took some time out to compare the sectionals of both the Kauto Star and the King George.
I was mostly interested in finding out how quickly Thistlecrack had covered the long distance from the 4th last to the 3rd last. I fully expected he would be faster than the novice Might Bite as that is when Thistlecrack pulled away from Cue Card and the rest of his field.
I got a surprise: 4th last to 3rd last Thistlecrack 32 secs Might Bite 32 secs, both took 13 seconds between the 3rd last and second last but from the 2nd last to the last Thistlecrack was 2 seconds slower than the novice.
Granted from halfway between the 2 fences Jacob had a rush of blood to the head but surely it wasn't an 8 length rush of blood.
Safe to say Thistlecrack was slowing down something that seemed to be backed up by how much the others gained on him close home.
Another factor which adds even more interest is that Royal Vacation and Cue Card covered the distance of 4 out to the winning post in exactly the same time yet Royal Vacation looked to be going much slower
I took a look back to Cue Card the Previous year the ground was massively slower which was reflected in Faugheen's time and Tea for Two's compared to this years races. But the real tell tale on time. Cue Card and Vautour covered the last 4 fences 1 second /4 lengths faster than Thistlecrack.
Perhaps Thistlecrack had more to give but the way he travelled with the choke out as you said, I would have to question just how much more/ I hope for his sake I am wrong because you wouldn't win a Gold Cup on that form as it has turned out to be one very poor renewal at the end of the day.
I certainly wouldn't take bets on there being nothing that can get to Thistlecrack in the Gold Cup. He's obviously very good but skipping round Kempton and never being put under pressure is not the same as 16 runners vying for places and 1/2 dozen wanting to be up with the leaders. That said he's been there in a World Hurdle and at Aintree and he never turned a hair.
Looking at the betting I do struggle to find a danger bar Don Cossack who I would back if he ran but Gold Cups often look that way but seldom turn out the way they look on paper
I am in no way crabbing the horse just stating the facts instead of listening to a commentator telling me Cue Card was fighting back valiantly when the truth is he was running a stone below his best.
It's not that long ago when Kauto Star 8/11 only needed to turn up to win the Gold Cup and if there was a danger it would be Denman. He ended up on the deck when looking beat and the unfancied Imperial Commander 14/1 tore denman a new backside and Kauto Star won 5 King George's. So caution is the name of the game there's a lot of even money shots you could back in much easier races