I watch the occasional The Grinder episode, but it is all about Rob Lowe. I enjoy his awkward comedy routine. It isn't even all that different from his Parks and Recreation routine (different premises, but same mannerisms). I believe Fred Savage has been cast as the slightly annoying, too serious and close-minded for their own good character ... even when they have a point. Rob Lowe's character probably wouldn't work without Fred Savage's "Grimey" character.
At the same time, I don't feel strongly enough about The Grinder to defend it as anything more than a stupid, fun comedy.