How about this:
If you use a given collective position in a helicopter with all conditions equal except weight, the heavier aircraft will have a higher rotor RPM and a faster rate of descent.
If you use a given rotor RPM in that same helicopter, the higher weight helicopter will have a higher collective angle.
The item that changes will be the autorotative regions of the rotor.
A helicopter with identical conditions except for MR RPM- lower RPM (within limits) will descend slower.
A helicopter with identical conditions except gross weight - heavier acft will glide farther.
If you have been taught to hold the collective against the floor, in all cases during autorotation, you are still at the rote level of learning autorotations.