That's a good idea wren, but I know there's no way we could do that here. Our courses are hard (often 20 - 50 jumps a course - a LOT!) over hilly rocky terrain and we ride open which is a true foxhunt pace which means nearly no walking at all. My horse is on a 16p feed (in combination with a 12p and high fat feed) to keep his protein levels up for the amount of muslce mass he uses each pace during heavy season and our paces are usually 12 miles long or so. About 1h 30m - 2h for open division so certainly a lot of speed and work there.
Jealous that you get to go twice!!! It sounds like a great idea!