Originally Posted by lexxwolfen
Regardless of what it is, it's generally not a good idea to have a horse stepping behind and across which some do without some forward movement. Better to start with a half pass and gradually take the forward movement away then build bad habits.
Same as Piaffe, it's trained with the horse inching forward and eventually the horse can do it on the spot.
To me a side pass is more useful then a half pass. If you do gates a side pass is essential while half passing is of no use.
If you want to hand something to another rider, again side passing.
I do use half pass when moving from one side of the trial to the other or for moving him away from the edge of the highway when road running.