At ~150lbs, I run 45psi on my commuter MTB. On my trail MTB, usually ~30psi. I don't even want to know how bouncy and choppy 50+psi is on trails with the MTB. Just to clarify, you mean sacrificing traction for tire safety? I say just carry an extra tube/air. Because at 50-60psi, I'd think you're sacrificing personal safety with what must be a really choppy, bouncy, ride with poor traction. I'd sacrifice a lot of tires before my own safety...