Dive should only work if the critter is Airborne.

[Essence]

Not that I think Wyrms and Pegasus need a nerf, but this is strictly common-sense: webbing a Diving creature should remove Dive. 

Just a thought.

[QuantumT]

I think I see where you're coming from flavorwise. If you want, I guess you can think of it as a diving tackle kind of thing.

Balance-wise, definitely not.

[Hyroen]

I --could-- see Dive working for Water creatures. Airborne doesn't quite apply to them.