Well I guess I have to chime in with my 2 cents, in my 16 years of maintenance experince and countless trips to a lot of unimproved landing surfaces, dirt, volcanic rock, rock and soft ground conditions. I have never had an FE or any other crew member for that matter come up to me and ask me to lower or raise the tire pressures. We would set them at 93 +/- 5 and call them good. I guess I just got lucky and never had to dig an acft out.