I am a die-hard supporter of the 4-knob layout for two pickups, in all seriousness. The variety and QUALITY of the available tones makes the admitted live squirreliness worth the trouble to learn. Leave the switch in the middle, set the neck pickup to 6-Volume and 10-Tone, and the bridge PU to 7 & 7. You can alter both the treble bite and the midrange fullness quite independently, by manipulating the three knobs not up full. Essentially, the neck PU turned down serves as an inductor to pull some bite off the bridge PU without losing upper-mids. But you can get that too.
I learned this one early on, and it's pretty clear from watching videos of the old guys - pre-pedalboard days, dinosauric I know - that they were all over the knobs. This setup is even better if you have an on/on/on series/tap/parallel switch on the bridge PU, because you don't even have to move the knobs to get three different volume and tone levels to mix with the neck. Of course you can't be sloppy, but the guys back then played first and danced and posed second for the most part.
I lived in Austin from 1981 to 1987, and there was a strong ethos towards a setup consisting of guitar-> cord -> amp. And the few Gibson players there knew all the knob tricks. (David Grissom, Eric J. sometimes, David Murray-not-the-saxophonist, he had a lovely blond 335). Hell, listen to Clapton back when he had The Force, '65 - '69.
If ever there was a guy who knew his knobs, here it is right in front of you, OK? First, the Live at Fillmore "Elizabeth Reed." Which some hold to be the best guitar solo ever recorded. Which sounds idiotic to me, but it does mean it's prolly worth a listen at least. And if you can't hear the moves Duane's making on the knobs in the solo which starts at 7:45 or so; sure - what good are knobs.
http://www.youtube.com/watch?v=DcpwMZKPsQM
Do you hear the fundamental difference about 9:10? Right at 9:36 it changes again, and at 9:55 he pulls the bridge PU all the way up. At by 11:00 he's changed it again, and again at 11:40.
Now, I had heard many times that the "Live at Fillmore" was recorded on an off night, which I thought ridiculous until I started digging through sugarmegs.org. I had thought that the harmonica player was superfluous and having read Duane's opinion that Dickie Betts was one of the best guitarists of that time, I thought he was just candyflossin' him. But as it turns out, there are plenty or examples of Dickie Betts on fire, and those nights also put the torch to Duane's playing. For example, the actual last closing night of the Fillmore, 6/27/71:
http://tela.sugarmegs.org/_asxtela/AllmanBrothersBand1971-06-27FillmoreEastNYC.asx
Someone has kindly extracted the "Elizabeth Reed."
http://www.youtube.com/watch?v=IS4xjQXTUYw&feature=related
Duane starts his solo at 7:58. And that's why you want four knobs, and that's what a Les Paul is supposed to do. If that and the "Whipping Post" from that night don't raise the hair on yer neck & yer nads, you need to stop waxin' so often, metroboy.
"It's on MY first album," sez Duane:
http://www.youtube.com/watch?v=eshNVYygv-s&feature=related
These songs excerpted on YouTube sound like typical low-grade Mp3's to me, the cymbals are harsh (dead giveaway) and the EQ is off-kilter. The sugarmegs version sounds much better. Yet, even so, here at 1:44 Duane smokes one for the ages. And DAMN Dickey's on (left earphone), yes, use headphones. In some concerts Duane would "relieve" Betts if he went noodly (or robotic), but no need here. The MONSTER starts lurking about 9:30 in.... it's like a bow, drawn tighter and tighter. The whole song is a fudging lesson, kids. Scorn it foolishly.
There are what appears to be 35 - 40 pre-death ABB shows at sugarmegs. Yippie.