I stripped off all of the fourth axis hardware today for the right anterior leg. This is a pretty risky move, and I've been procrastinating for some time as to whether or not to do this. But the pros for going back to a three axis leg far out weigh keeping the four axis design. If however it turns out that the four axis design would have been better I can always re-instate it, with a simpler design without the need for the belt driven encoder.
About 13Kg of parts removed including the ram, should save a significant amount of machine weigh plus help with leg position control having less weight at the tip of the leg.