Pretty well everyone who adds an electronic drive to their lathe will do it only to the lead screw regardless of Electronic Gearing, ELS or CNC.
I get all that John. Yes, it's an option to go that way.
But my half nut is only designed to handle threading. If I started to use it for feed too, it would be toast in no time. My lathe is a 14x40. Not big, but not small either. The feed and threading operations are separated for a reason.