Yeah, I wondered about that too. Temps at the base didn't seem different more than a degree or two. To be honest, I probably won't run without a sleeve at least below the hold-down again. It looks cool and made for a nice pic, but when the avalanche comes, not so good whether you're sealed or not. There could always be a pinhole in the LET lurking somewhere.
Edit: Now that I think about it though, I don't think I had as much DIce left over this time, for pretty close to the same amount of time benching the same benchmarks.