Harold, if I keep my oven at 600 for longer than about an hour, my self cleaning light comes on, so I'm thinking self cleaning peak temps will range from 600 to 800. I don't think I'd feel comfortable about pushing my oven to 800, though. Basically, ovens are wired with heat resistant wire. If the wire hits a particular temp, the coating will burn. They're insulated to protect the wire, but this insulation doesn't guarantee you extremely high temps.
You read a lot of stories about people running the self cleaning cycle during the holidays, only for the oven to die, leaving them with a turkey crisis. Self cleaning temps are hard on ovens. I think once or twice a year is not that bad, but hitting self cleaning temps once a week for pizza is most likely going to shorten it's lifespan. This is why I'm a huge advocate of shortening baking times with thicker, more conductive stones, rather than extreme temps. With some especially weak ovens, you have no choice but to use a thick, conductive stone AND an oven mod, but the oven mod is never that drastic- 100 degrees at the most. With the right stone, there's zero risk to the oven.
I see from your earlier posts that you were originally from Pittsburgh. What were your favorite pizzerias there? What style are you striving for? The style dictates the bake time, which, in turn, dictates the oven setup.
The most popular method of measuring oven/stone temps is an infrared thermometer.
