If you cast its against 3 elves you get a card, but if you cast it against 2 elves + someone else and they block it you don't draw a card. Not sure if either situation is a bug but its pretty strange.
Hmm. Blocking a card usually eliminates ALL effects on that card. So, say, Block a Bungled Bolt and the caster suffers no backlash, even though that seems weird. Drawing a card is another effect on Elvish Insight, and "the card is Blocked," so it seems the code is operating as intended. Again, even though that seems weird. Edit: there's a complicating factor in how this is a card with multiple targets. Kinda like Flash Of Pain. I still have a hard time understanding how Blocking with multiple targets should work.