Don't you need the apron for the thread dial? Or is there a way to improvise a thread dial, you know the one that comes around to time your reengagement.
In the past, when threading, I could not disengage the half nut or I would lose my place.
So the procedure would be to take the first pass, stop the machine, back off the tool, reverse the machine by hand back to the beginning, feed in tool, start second pass. A major PITA.
I think that's worse than having to change the gear sets. Actually i would rather have to change the gear sets than futz with that procedure to produce a thread. I've done it, but its tedious.