Tom, i've had no problem with green pads.....work fine....one thing about varnish is that if you sand with the grain, you can get away with a wide range of abrasives between coats...up to 125 grit sandpaper if you need to remove problems...down to very fine wet paper or steel wool.......you just don't want to varnish over a hard gloss.

Actually I've read that the optimal sanding grit for roughing up between coats is 200.....rough enough to provide the next coat to get a good grip, but not so rough that you end up removing a lot of good varnish...using finer abrasives between coats doesn't really help you get a smoother finish and actually reduces adhesion between coats...

by the way, if you recoat soon enough, you don't even have to rough up the surface at all......called "hot coating"......the first coat is usually 4-6 hours cured....still soft but not tacky....

good luck