Hi Cranky yankee.

I think you may find there are more square rig sailors here than you think, but the essential point is that folks song, including shanties, do 'orrible things to both the English language and technical terminology to get a good metre and rhyme. As Bruce O points out there is no evidence that the original was penned by a seaman, and even if the phrase originally used was "overhaul your davit tackle fall' as you suggest; convention and usage take precedence, as in most things.

Pete M