I have never seen or heard of the VFO system, but I'll offer my take from what you have posted. This looks like some kind of patent work-around or someone maybe trying to re-invent the wheel, at the least it's Parker marketing at it's finest. I don't see why this would be classified as an open...
If you had anti-cavitation checks on the working ports of your motors, then the outside wheel when turning would be able to pull the extra flow required. The outside wheel motor would have to be in an overdriven condition and would temporarily turn into a pump, while the inside wheel motor would...
