Subdivision symmetry result

When I move the middle symmetrical subdivision boundary line during subdivision symmetry, it produces result A. I hope there is an option to produce result B


AB.3dm (9.2 MB)

Then don’t move the middle loop, only the loops next to the middle loop.

Subdivision symmetry also requires such an option


2222.3dm (10.9 MB)

I have been using segmentation tools for modeling, but some features are missing some options. If the segmentation can be optimized well, it can improve the efficiency of modeling