GMM wrote:


I guess a small radius would solve most of the wear problem without
causing enormous stretch problems with the carpet but is there
something else I can use, other than a router, that would allow me to
form a radius all the way to the edge? A hand-tool based approach
would seem unlikely, simply in terms of getting a good regular finish,
and I'm not sure that an angle grinder, SDS drill or chain saw would
necessarily do this job, before anyone suggests them.....

Beg, borrow or steal a laminate trimmer (such as Makita 3703) which
doubles-up as a compact router (make sure it takes standard 1/4" router
bits and make sure that the bit you use is rated for 30,000rpm). Use
this to round over as much as you can, then sand the rest.