Yea I found it strange too. I did my very first Ht there and had no probelm. But I know the last time I went there were a lot of stops on the prelim and intermediate courses. Plus the course is curvy and im afraid my lazy horse couldnt make time.
Someone who is advancing to Prelim, should understand that it isn't about riding the clock, it is about riding each indavidual fence. And who cares if you get time penalty points, it's about the experience and staying safe.
I know its not about time. But the old man's already a little pokey. Of course id take a clear round over making time any day. Just I know the course is very windy (cant spell) while RH is pretty stright usually and has better footing.