Well, as I said, my Power Gear is a 4-jack, system but only 3 points, If one jack sinks then either the rig tilts to that side (if a rear jack) or toward the front) if it's a front jack) as the front jacks will self-level to match the rear
now, I have spoken with folks who had the cross member torqued by their single front jack, They insist they followed the instructions, though I assume it is possible they did not, but still the front cross member could not take the load.
Frankly I do not see how it could torque the frame, unless the cross member gave way
I'm very fond of the system I have as this discussion goes
There are other issues I'm not so fond of, but hey, each system has it's advantages (They are Power Gear v/s HWH issues A couple things about HWH I like better than PG, However when it comes to leveling the rig, I like PG's method of doing it)