I had a DP and IC with no tune for a few weeks on stock clutch, it was OK. Doesn't seem like much power got added although it definitely felt like the turbo spooled a little quicker. It definitely sounded better than stock.
I don't think it's going to make your clutch slip just by doing it, although some people slip on stock power so if you've got a junk clutch from factory it's doomed regardless of whether you add power or not.