Originally Posted by Jsiegs

yeah, I'd like to, and I do try to flatten my back sometimes. It feels more comfortable/powerful in my very anecdotal experience. However, my main issue is numbness and this tends to exacerbate the problem. I've been on a wide range of saddles and experimented with different angles etc and this saddle/angle is my best compromise between everything I've found (e.g. I could nose it down and relieve some of that pressure but then I'm sliding forward constantly which is annoying and puts me on the nose where there's more pressure). So the arched back seemed like the lesser of the "evils". I can still flatten out when I feel the need though, just not for too long.