This has been a conversation I've been following with interest from the start, two years ago. I've been leaning against my pack, which is leaned against a tree, and using a closed-cell foam sit pad that weighs about 1.5 oz. for at least a decade now. It's always been quite adequate, but decreasingly so. I think I'm ready to start experimenting with other approaches on day hikes, where it is easier to justify the weight.

Anyway, if anyone has further thoughts to share on this burning subject, I promise to read them with great interest.