cover wrote:
I wondered how something like that might work (a diversionary concept
to draw the roots away from the slab). In the experience of those of
you who have cut these roots, was an axe the best approach?

Don't try a chainsaw. The blade will last only about 15 seconds until
it is totally dull. That happens even if the dirt is dug out fairly
well. All it takes is a momentary touch to kill the blade.