The basic theory is sound enough; there's at least one company out there making something along these lines. They're called the
HitchGate,and are a) extremely expensive and b) inadvisable for use if actually towing. Not to mention how this would affect departure angles...
It's not a bad idea per se, but probably not totally practical for the trail. Then again, if you're not doing anything involving high ledges, rocks, or washes, it could work out OK. There's a review of one
here you may want to check out. The Range Rover setup looks very similar.