I assume he's referring to these things:

http://store.catsailor.com/tek9.asp?pg=products&specific=jmorenhnf0

I much prefer these to dogbones. Easier to get on and off, and much less painful when they hit you in the face.

I have adjusters on the rear trapezes of my boat. I find it really useful to be able to lengthen the trapeze when trapezing right at the back of the boat going downwind.

Paul