Turn off/on stretch on ribbon spine rig

Hello There! Does someone know a trick to get a stretch toggle option on a ribbon spine system. I would like to avoid, using a ik spline as a base, i tried to play with ‘lock curve length’ but the result is pretty funky. I also tried using some curve attach tricks to extend or compress a curve and gather good parameter for extension and compression but it’s quite tedious. The basic idea is to get the non-strechy ik spline behavior but for position only, without have to compute ik iterations. Is there a way with maya vanilla nodes??

Thx for reading!