From March last year up to the festival this year, RP had just four runs over hurdles. His ORs went:
123, 136, 145, 156.
By any measurement that has to represent improvement. According to the IHRB site he's still rated 156 so you could argue that the curve has reached its plateau. Perhaps the database hasn't been updated yet.
I agree that the way this race was runs renders it largely negligible but I've looked through it for angles with which to tag a meaningful rating for each of the principals. It looks like Maruco has done likewise and reached similar conclusions.
Whether I would rely on those ratings to be supported by future form is another matter.
Big field handicaps tend to be - though not always - more truly run and the form tends equally to be more reliable.
What many punters (and pundits, sadly) seem not to appreciate is just how much winning they take, most especially modern-day festival handicaps. Horse handicapped to win decent Saturday TV handicaps are lucky to run into a place in the main festival handicaps nowadays. But because the handicapper knows he'll be crucified for raising a narrow winner 14lbs he lets them off relatively lightly thereby enabling connections to campaign him for a race a further twelve months down the line.
What happens in between is that these horses come out and run when they're only fannying about at home and not being trained seriously, getting well backed because they're festival winners but disappointing so punters end up questioning the value of the form.
Of course, sometimes the race takes so much winning it leaves its mark on the horse (eg UTPT after its second Ultima) that it's simply gone.