[QUOTE=vicarious;7842678]
Here you go folks, quit arguing and read.
I read and will argue a bit! 
Instead of saying ‘‘cannot reach with the shoulders’’, it would be more accurate to say that the horse cannot lift its withers and free its shoulders thus putting the weight further back on the hind legs.
The reaching part comes from the hind legs. If the horse put all its weight on the front (with its head too low, closed) and is blocked in the front, the back won’t round up and the horse won’t be able to ‘‘push the load’’ at all. The horse will ‘‘pull itself’’ with the front end and drag its hind legs behind instead of pushing forward for that extra reach. I think the expression is ‘‘strung out’’ for that?
I compare it to a ‘‘front-wheel drive (traction)’’ which equal front to back riding vs a ‘‘Rear-wheel drive (propulsion)’’ which is the back to front riding!
[QUOTE=raff;7843458]I think it’s / collected steps into footprint/working steps over/extended steps clearly over.
Undertracking (except in P/P obviously excepted) is a no no.
Probably better to look further than USA guidelines, so as to be sure nothing has been lost in translation? I hope that’s ok to say :uhoh:[/QUOTE]
Rules say nothing about tracking up for the trot, only for the walk.
But IMHO, I wouldn’t think collected steps need to track up much as long as the horse remains supple and forward.
And there is a lot more to be judged than the tracking up.