If my memory serves me, JB discussed something similar in a seminar for one of the SA Breeders' Cups ages ago, the "Poly Pop," I think.

The gist, from what (little!) I remember, was about what you describe: a horse who runs frequently on dirt sometimes jumps forward in their first try on an artificial surface. Can't recall more detail, sorry.

Try the 2008 or 2009 BC seminar.