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Anyone here have any clues how "latitude" came to mean "flexibility," as in: We've got a lot of latitude on this design.
And why was it "latitude" that took that role and not "longitude?" Could not find anything at my usual etymology sites.
Ngrams shows "lot of latitude" being used starting around 1915, but didn't find ANY cases of "lot of longitude." Don't know if that helps.
[Edit: Just realized I misspelled "flexibility" in the title of this post. For some reason, spell-check doesn't operate there. Would be nice if we could edit titles. Can a Moderator correct titles?]
[Edit: It appears the title has now been corrected. Maybe a retroactive automated spell-check? Or was it a Moderator? How does that work?]
The OxED has this entry 'latitude = flexibility':
3.
a. Freedom from narrow restrictions; width or liberality of construction or interpretation; tolerated or permitted variety of action or opinion.
1605 Bacon Of Aduancem. Learning ii. sig. Dd4, Allowing..that Latitude, which is agreeable, and familiar vnto diuine Prophecies, being of the nature of their Author, with whom a thousande yeares are but as one day.
The 1605 date is 200 years after 1. and the geographical use below.
The OxED has this note (edit: the preview did not seem to have a problem with the Greek characters that are now in question marks):
[In their original geographical use latitude (Latin latitudo, Greek ??????) and longitude (Latin longitudo, Greek ?????) meant quite literally the ‘breadth’ and ‘length’ of the oblong map of the known world; this literal sense remained even in the expression ‘degrees of latitude and longitude’ (?????? ??????? ??? ??????). By a natural development the terms afterwards came (in late Latin, apparently not yet in Greek) to denote the distance of any place, in the breadthwise and lengthwise direction respectively, from the circle assumed as the origin of measurement.]
I note that someone who is flexible is more willing to go to greater lengths (or go the extra mile) than someone who is rigid or inflexible. And, although we do not use the word 'longitude' in this context, it does seem that flexible seems to apply to both directions ('breadth' and 'length').
Heimhenge said
Or was it a Moderator? How does that work?]
All Moderators have Great Powers, but a moderator, like me, refrains from using the powers he does not understand. 
Mwa-ha-ha.
Spoo-poo-poo-pooky.