Personally, I'd be just as worried about aggression from the barbs. Paradise fish do have long enough tails to present a target to the tigers. If the tiger school was big enough (at least 12), I suppose you could try it, but it isn't a combination I'd want to risk.
This isn't personal experience, though - I have friends with these fish, and I was interested in them myself for a while, so I did a bit of research, but it's not my experience. :)