I use carbide toothed table saw blades, sliding compound miter saw
blades and a sh*t load of router bits - all on wood. Clearly
cardbide cutting edges WILL can make glass smooth cuts, both
ripping, cross cutting and routing - including acrossed
end grain. Of course, in these applications, the RPMS are
in the 5K range for saw blades and 20K-30K for router bits.
Knots don't seem to be an issue with these cutting tools.
Perhaps the rpm range of most turnings is the problem.

As for the surface left by a carbide cutter, what I was talking
about is roughing, both outside and inside a piece. Use the
finest edge tool when it makes a difference, and the carbide
tool to do the grunt work required to get cose.

But if you enjoy sharpening . . .

charlie b