OK, if I understand the physics here, 212 is as high a temp as you can get at normal atmospheric pressure, right? To get higher temps, you need some way to increase the pressure, like a pressure cooker.
Until I get a burner and start some REAL boils, I start with the lid on the pot. I lift the lid regularly to let the DMS and other evil spirits out, and to check on the boil. Once I get a decent boil, the lid stays off.
Now that I have a 5 gallon pot, getting 4 gallons to boil in it takes FOREVER, even with the lid on. Our glass top stove sucks. I'm working on a heatstick, and that should help until I get my burner.
Just how important is a "rolling boil"? As long as you are at 212, you are boiling.