Kevin, I guess my decision to swage, rather than ream is to keep all of the brass intact. Reaming is a surgical solution, while swaging is mechanical. All of the brass remains, and if one decides to ream further on, at least the majority of the interference to smooth re-priming has been eliminated. I suppose it's a function of my minimalist approach to working brass...do no harm!
I suppose that one could over-swage a pocket. It seems rather hard to do as the swaging nub fits into a primer pocket, and then stops. Regardless, I swage just enough so the case drops freely off the nub with little to no effort. Naturally, everyone has to set their own level of comfort in this artform. I do 90% of my priming by hand with the FA Perfect Seat Hand Primer, so I can tell when I went a little light on the swage. Since you're the only one affected by your decision, you get to choose how to open up those crimps.