Most of the poi stuff can be done with a centre grip and a bit of contortion, I think, with a bit of practise. The end grip is good for getting the feel of moves, but then you can *mostly* move back to centre grip. There's a few moves (e.g. 3 beat weave) where to do it you have to either open your hands so the back ends of the staffs can pass between them or do half of the move with one hand locked behind the other staff, so it's a translation rather than an exact copy of the move, but hey, it's a different toy...
If you're going to hold the ends you might as well do clubswinging or something silly
