It wouldn't be apparent for years, if it happened at all.
Fab Five is legendary because they had three guys go onto the have massive NBA careers. Classes are measured by their college and NBA success (which is why the '13 UK class doesn't hold water with Randle being the only legit NBA guys from that group). UK would have to have three or four guys go on to have the types of careers of Howard/Rose/Webber, and they'd also have to make a Final Four in their first year like the class of '91 did at Michigan.