Idiot, NO and as a matter of fact, I have seen a couple of good installations like that and a couple that I think are less desirable.
1. BUILD LOG: King Midas mill conversion is one way to do this type of mill in a manner that you suggest.
2. I thought I had another site bookmarked and the author was Jeff ?? and he was selling plans and parts also. As I remember, it was Home Shop or something like that. He gutted the existing system and put a rotating ball nut and servo up in the cavity of the head. Very neat installation.
3. I did mine by tightening up the clearances on the pinion and the worm wheel of the fine downfeed and get minimal backlash.
I have seen some others, but from an engineering point think they move the ball screw out to far and use to flimsy a bracket. This increased leverage looks to me to provide flexibility and poor accuracy.
Whatever you do, you can make this into a very capable machine if you live within the limits of rigidity.