For a brief time (along about 1992), Hobie made a one-piece, rear-lacing tramp for the 16. It was based on the tramp design for the Wave and is still used on the Tiger and FX-1.
The problem was that you couldn't get them really tight - and the 16 likes a really tight tramp to help with frame stiffness.
There are no differences in the boat frame between a 3 piece and a 1 piece tramp.