A true topping lift runs from the back of the boom, to the top of the mast, and back down. The clip that your refering to that is swaged onto the backstay is not a topping lift. I am not sure what the proper term is for that. If you don't have a rigid boom vang the topping lift makes life a lot easier as you don't have to clip and unclip the boom as you are raising or lowering the mainsail.
Courtney is My Hero
If a man is to be obsessed by something, I suppose a boat is as good as anything, perhaps a bit better than most - E.B. White