I've spoken to pusga and gargon and we're not overly inclined to validate this. It's one of those things that no ones done because it seems pretty obvious we'd invalidate it, and they're not wrong for assuming so. The idea was cool, but I'm afraid it may be a little too iffy to count.

Main reasoning is that the arm pretty much stops being 'you' once it's dismembered so it doesn't particularly count for the jump. Pretty much the same reason skeeting for it doesn't count, it's not really a whole tori anymore if an entire separate part of you reaches the top.