Not relevant as we were referring to moving lights, not the focus (well, I was anyway!) and inverse square rule in general. But yes, on an enlarger the re-focussing will affect it a bit. but only because it will also change the coverage so the inverse square rule will still apply.
"People who say things won't work are a dime a dozen. People who figure out how to make things work are worth a fortune" - Dave Rat.