I've always turned my bikes upside down. Quite funny on an evening winter club ride a few months back. It was a kin to a comedy sketch, or a joke, you know..." How many ....... Cyclists does it take to mend a puncture " . We'll in this case 5!!!! It was indeed a comedy of errors, and despite my laughter, and pleadings, they refused to turn the bike upside down to make life easier. Anyway, I'll always do it. when I get a visitation, I know its not a quick swap. So wheel the bike to the verge, out with the tool kit, flip it over, on with the glasses, then INSPECT! Quite often the offending item can be spotted, tyre marked, and partially removed, whilst still in the frame, and problem sorted. Then when its all back together, a slow rotation of both front and back wheel to INSPECT for any other likely culprits. Also now with discs, on Olive, I find that if the wheel is removed, then when reinserted, the wheel can be spun as the qr is tightened, this ensuring the brake is not binding.
Yes I know ...what about if its dark....what about if you cant find the cause ...etc etc.I find that turning the bike upside down, renders it helpless, Like a sick animal, awaiting my delicate , undivided attention, as opposed to rushing the job thro, possible bending mud flaps, mudguards, derailleur etc. . Flipping the bike over sets the scene for an unhurried operation , you wouldn't want to rush it and get it wrong.......BUT you see, this brings us to another question, do you patch, or do you swap?? I always patch unless its raining/ snowing or dark. ......or both. Flipping the bike back over again I get a sense of satisfaction, of job done, a bit like finally closing the bonnet of your car after an oil change/service.