the thing it helps most with is hitting rails unnatural (opposite foot forward)
i couldnt hit a handrail unnatural to save my life 2 years ago, but then i practiced both ways on my setup all summer and last winter i was doing handrail DFDs unnatural. /claim
as for switch ups and 270 on/off, I found they are still way easier with the longer, better rails at the mountain anyway. my summer rail is too short to kfed.