Bump and grind simply isn't the same past age 60. Bumping usually involves inadvertently whacking a piece of furniture and grinding is something you do to your knee while walking the dog. But still, this Monday, men and women over that age will gather at the Nets practice facility to try out for Brett Yormark and Petra Pope's latest marketing creation: senior Net dancers. No skimpy outfits just sweatshirts with their age on the back. Post gossip columnist Cindy Adams has all the details.