...covering a lot of ground in one position doesn't mean anything. Switching positions is an integral part of technical development on the instrumnet, and if you try and get around that just by stretching, you're missing out on a lot. But that's a debate for another thread.
Objectively, I have yet to see anybody, save for pivoting (which I can see as a valid method of implementing OFPF), show me a way to play in the lower positions OFPF without bending the wrist to an absurd angle. Any doctor will tell you that much stress on the wrist at that kind of angle for any prolonged length of time will increase the risk of injury. The bent wrist is what is wrong with it. Other considerations simply come from body awareness and common sense (why use muscles that you don't need to by stretching? why fatigue the hand when it isn't necessary? etc.). OFPF diehards will dismiss that, but can't dismiss the first one. Show me your own demonstration of the safety of OFPF and I might be swayed in my opinion.