Yes it does Annette! Thanks! I will try that next time. Though this is the first screw I've needed an easy out for a sewing machine so it may be a while before I get to try it!
For the moment, DH managed to get the hook off the shaft - so the shaft isn't at risk anymore, but the set screw is still stuck. It's marinating in the high test for the night and he'll take a crack at it tomorrow night after work. Poor little featherweight!
I'm going to ice my wrists and lower back tomorrow - this one really took a lot out of me for some reason! - and take it easy til he's home to try again. The Spartan cleaned up well and fast. Need to put a spare motor on it to test sew it tomorrow.