They would start the tour with both sides having a mix of both guitars and, over the course of the tour each guitarist would end up with only his sound coming from “his side”.
There is no rule. Every sound person has their own approach and its either great or its not. If its dueling gtrs I can see a decision to do that wide. But I basically left FOH to monitors, basically because at the time it was the hardest job few wanted. Which left a lot of work for me, while the rest fought over FOH so they could be seen at the helm.
Every once in a while I’d go in as system operator where the band engineer mixed and I sat with him to babysit the system and not allow someone to cook it. So I watched some band engineers mix FOH, some were just great, some sucked. Its their show, but if they sucked so bad it became a problem I’d remove them and take over. I only had to do that a few times.
Sounds like he was good. If you and I mixed the same band it would prolly sound different. In the old days, with limited gear, in an arena, I’d have 100 feet between speakers, snd prolly not go so wide.
When I had the EAW 850 rig, where the stacks were semi-circle display I went much wider, because audience on the right could hear the stacks on the left. That was a fun system, one of my favs. Because I could do a full stereo mix everyone heard. Mixing a symphony in stereo was cool because I could steer stereo to each section location on stage.
Pink Floyd Animals tour, they used the Flashlight system and mixed that tour in quadraphonic. That was badars.
Tom Petty took out the EAW Anya system, extremely expensive, it’s a digitally-steerable column loudspeakers. It hangs straight and forward, but uses phasing to steer the sound where ever you want. A stereo mixing dream.
In the 90s Rolling Stones used the DB Sound X box system, it was displayed in semi-circles, again great for stereo mixes. Funny thing about their engineer, he does NOTHING. Barely even EQs anything, if at all. Puts mic in front of instrument cabs, turned ch on throws faders up, thats it. Shocking. The band creates their own sound. Barely, if any, stereo mixing.
For me, mixing stereo depends on several things. Width of seating, width of speaker placement, type of band.
Most engineers, especially monitors, are thinking from second to second for hours. It would take 2-3 hrs after show to slow my brain and adrenaline down. Why I do things for games, my brain loves to haul ars, keep busy. Ya get conditioned. Why instead of partiesI went fishing to wash it down the drain.
I saw Travers as audience in 77 I think. Was a big fan. Years later, mid 80s, I met him when he was playing smaller venues, I was system operator.