This is still a problem. I've been waiting a good half hour now waiting for Topogun to figure out how to undo moving a single vertex. The cpu usage is a constant 25% which suggests the process is single threaded. Perhaps whatever function is going on, could be multi threaded?
I have a dense basemesh that is about 22k quads (perfectly acceptable for a quality basemesh).
Its funny because the new brush tool is far faster at updating the points than whatever procoess is used to update the geometry after welding verts, and undoing them