I would not say that the park are responding to market conditions. They are randomly changing direction presumably because of the change in director.
The park seems to have no long term vision and doesn't consider that there investments are going to be there for 20+ years. This ride is another where the same mistake has happened again.
Thorpe is going to look incredibly dated in 10 years time without serious investment. Not only should they consider replacing Colossus by then but also, Saw, IAC, walking dead, Angry Birds, DBGTROTD, samurai, vortex, slammer, and loggers leap. I highly doubt Merlin will be spending the kind of money ontop of new investments to make up for the rapidly aging park they have built themselves.