I've heard this guy play and yes, he's effing loud, louder than the rest of the band - guitar was THE loudest thing in the room.
I totally understand the need to play loud to get a certain feel out of the amp but there's is a limit for it to sound good in a band context and in the FOH mix.
There's a couple of things that can help.
1) Never point the amp into the stage, towards the singer. You'll get away with more volume on your side without having him complain.
2) Place the edge of the 4x12 at the same depth as the snare drum or slightly behind it so the drummer can hear you but not so loud that you're blazing in his ears. (this may vary from venue to venue and monitor mix)
3) Set the drums and guitar as far back of the stage as possible. That way, you can walk out to the front of the stage and hear yourself better than if the cab is right on your ass.
4) If you have a sound guy, DO NOT start playing until the drummer starts banging on his skins. That way, he won't complain about you as much.
5) You need a LOUD drummer.
6) Plexi Shield is a great solution.
7) Get a THD Hotplate and set it to -4db or -8db

Get a lower wattage amp
9) Get lower efficiency speakers
The only time I ever get to crank an amp and get away with it with no attenuator is with a LOUD drummer is a semi large venue (350 people) with a JTM45 clone or an Orange Tiny Terror (not as loud drummer). The JCM800 2204 can never be run without an attenuator, anywhere (for me).