Short answer no long answer yes. I have found the point at wich the arrow is registered as bieng pressed is earlier in FFR than Stepmania. So if I play one then go to the other I'm way off and it takes me a few songs to get used to it.
I usualy don't play the two back to back for this reason. But if I switch off every other day my overall performence inproves.
I would think it would depend on what your issue is with DDR. If it's that you cant read the arrows, then I would think it would help. If it's that you tire out... then no, it wont.
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