Chain reaction

In thinking about which pizzerias I should cover in this blog, the question occurred to me what to do about chain pizzerias. Should I review them or not?
The short answer I've come up with is this. National chains I won't report on at all. If you've had a Papa-Domino-Hut pizza anywhere, you know what it's like already. I can assure you it's the same here as anywhere else. If you haven't tried it by now, then you're probably not interested anyway. For that matter, if you're reading this blog you're probably not interested in what their pizza is like.
For local and regional chains, though, I will try to get to one (preferably the original, if it's still around) location of each. Now I know that some local chains have more locations in the Rochester area than do their national competitors (the Rochester White Pages list 10 Domino's and 17 Salvatore's, for example), but if a reader has just moved to this area, or is planning to visit or relocate here, I figure it may be helpful to provide some info on the local chains.
Also, if I were to leave out the local chains, the question would then arise, what about a pizzeria with only two locations? Is that a "chain"? Most people would probably say no. So what would be the magic number at which a pizzeria becomes a chain? Any number I could pick would ultimately be arbitrary.
At the same time, it would be pointless to visit, say, every single Mark's Pizzeria around here. Presumably they're all pretty much alike, or at least they should be. Hence my solution: one location per local pizzeria. Stay tuned.