I have always suspected that the hopping was caused more by the rubber feet on my original bipods. I surmised that since the rubber feet didn't slide, they hopped unless they were front loaded.
If you mount the bipod correctly, the legs fold forward, not backward, so they are stable in the direction the bipod hops.
(I'm amazed by how many shooters mount their bipods so the legs fold toward the butt of the rifle instead of the muzzle.)

I'll be waiting for your first test, to see if having fixed legs solves the hopping problem or if the rubber feet are the culprits.
Interesting experiment.