The spring never should have popped loose the first time.
I, too, was surprised I got the mainspring set again after removing the strain screw but without removing the side plate. Got lucky I guess. It seemed fine.
Later I decided to do a thorough inspection and removed the side plate, strain screw, and mainspring. Put it back together and again, it seems just fine.
But I don't trust it enough to carry it now and never will.
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