Hi Lynn >>At least with Peruvians, what is highly desirable when gaiting -- ie., enough reach with the back legs such it is stepping under the saddle area and is capping or, even better, overstepping by up to 12 inches the front hoof prints, really doesn't happen if the horse is ventroflexed, any more than a human can stride out with pronounced lumbar lordosis.
In fact that is actually the opposite of collection, if you think about piaffe - the hocks are very articulated (bending) and the hind legs stay right underneath the hindquarters to support the weight on the hindquarters. I see lots of gaited horses with a lot of overreach and while I would not say that their backs are necessarily ventroflexed in a stationary way, I think that the backs of gaited horses go more like down and then up to level but not 'up' and then down to level as in non-gaited horses. There is more downward flexibility, than upward, in nearly all the gaited horses I have met. >>>Sec. 1. Advance and Overstep Advance refers to a long fluid stride which easily covers ground. Overstep denotes the reach of the hind legs which should reach well under the horse with very little hock action either up or sideways. The preferred reach of the hind legs is between "capping" and 12" of overstep. Understepping will be penalized Advance should not be accomplished at the expense of elegance and/or leg action. This definition says it all - stepping under should not have hock action which means they are not looking for collection.... and maybe you are not looking at it in that way anyway and I have just misunderstood.. Robyn