I most definitely believe an aider flapping in the wind that was "new" to that deer could easily alert it enough to make it change course. I also think it has a lot to do with the location of the new interaction. Cameras are more readily tolerated near feeding fields for example than deep in bedding areas. Scent has a lot to do with that too, and the cameras do make minor noise when they fire. As you get closer and closer to hunting those reclusive areas, ANYTHING out of place is going to gain a mature buck's attention IMO.
A long-term habitat guy here in Michigan told me a funny analogy, but it really hit home.
Suppose you leave your house one morning, get on the local freeway, and a mile after you're on the freeway the car in front of you flicks a cigarette out the window. It gains your attention for a second, but no big deal. Now suppose you return home after work, and you head out to get the mail from the mailbox, and you notice a cigarette butt on the ground there (and you don't smoke, nor do your family members). This certainly gets your attention, much more so. No you head on inside, and there is a cigarette butt on the counter. You are on HIGH alert - something is completely wrong! Same item in every case, but where you see something unusual is a VERY important part of the assessment you make about the item. I truly believe deer are no different.