@ Seashore: what you wrote is not off of base at all to me...
+ 1 also about the idea that CNC machines can be programmed to add scatter.
And there's reasons to consider that all pickups are scatter wound to some extent. Some zoomed pics of coils on the Throbak website are pretty enlightning...
About the "repeatable" character: the patterns and typical TPL of hand wound coils are logically dictated by the gear and methods of hand winders... So there's a kind of "signature" in hand wound pickups, IME, with sonic differences depending on who wound the coils / on which lathe. That's why I've won a pair of Skatterbrane's during a shoot-out in 2012 on MLP... ;-)
To put in perspective the question, I'd just add that hand winding seems to often imply less tension or a varying tension. Logical to me, knowing how easily a thin wire can break between fingers and how tricky it is to feed the coil with a spool of wire placed on the floor...
When the tension is continuously or globally lower, coils have a lower capacitance but also a lower Q factor, making them brighter as well as more "open" sounding. That's something that many players seem to appreciate with single coils but giving mixed feeling with humbuckers, apparently. Hence the idea that HB's must be machine wound to sound right.
Where the pic gets blurry is that I know at least one hand builder able to wind coils with the specs of machine wound ones...
FWIW.