Interesting comment. I wonder what the effect would be on some of the top dressage combinations (Salinero?) of having to do a test on grass?! Could be quite entertaining.
Did he explain any further?.... is it because surfaces absorb the impact of the hoof where as grass bounces it back?... I'm just guessing that this is true....
He has ridden on grass before - he went to the PC Champs in 2007 in the open dressage - he was in the same section as me! grr, although he didnt win, got beaten by a lovely cob like thing - very happy!
If it's based on the kur he did as a demo at Badminton he might have noticed a difference in the timings against his music compared to on an artificial surface. I would image the ground in the dressage at Badminton would have been on the fast side.
Grass sure does ride fast when you're on an 11.2 - took daughter years ago to the PC champs to do dressage to music to an Elvis compilation. Thankfully we weren't in the same section as Charlie Hutton
Whole thing was completely out of tempo the whole way through because we'd picked the music to go with him whilst riding in an arena with sand and plastic granules. Then we had another competition in an indoor school and the music was spot-on. I thought it was just because he was so little, so the surface made a huge difference. Not just us then!
I was more interested in the comment that he came away from teaching with a nice wad of cash. I thought that was very rude. No mention that he enjoyed it or it was good to help people, see different horses, whatever. Sounded like he just did the teaching for the cash. Even if its true i thought it was a bit rude to say so in a blog!