Sure, you could animate it realistically even if you only use normal and transparency mapping-just make a lower res model and animate it to the mapping.

I'm a basketball player, and I'll tell you right now, each of the loops in the net doesn't move individually-they move in little stacks (Assuming the ball is swishing nicely through the net) so you'd really only have to animate each level, and make sure that the textures are properly applied so that it's a fluid anim.

If you really wanted to model it, I'd suggest making a lot of curves then either extruding along them or doing some dastardly NURB work.