The regulations apply to special events (think Papal Mass) and professional film companies. No one's going to roust a dozen photographers shooting big weird cameras, unless we/they make a nuisance. Then someone will (rightly) send in the park rangers and tell them/us to move on.

The birders routinely congregate in the Rambles with tripods, without permits. I've shot on tripod in Central Park for years, and no one has ever once questioned me.