Glen, I agree, the VB clothing is more versatile in that it allows you to layer clothing on top and you can use it while at camp. I'm not sure you could get away with just a shirt though, as when I use the liner, I don't see areas that have more "dampness" then others - I'd say it's pretty even. While I'm sure certain areas of the body expel more sweat then others, after a long night I think you would either have to cover up everywhere or face the consequences...just thinking out loud here, not from experience, so maybe someone can give us both some insight.
FWIW, I use a VB liner, but only because it comes in at 5 oz vs the clothing which I believe is substantially more. If you find something lighter, let us know! :)