That's why I highly recommend fermcap foamcontrol drops...no boilovers no matter what...I have filled both my turkey fryer and my 5 gallon stovetop pot to about 3/4 inch from the brim, and had no problems..I've even been able to go take a nap for part of the boil...
Thanks Revvy, I tired this on Tuesday night. I was boiling on the stove within about an inch of the brim and no problem. I actually got some other stuff done while the wort was boiling.