John,
Probably because, whether by foresight, long practice, or instinct, you have adequately taken care of this first basic step.
I am not suggesting this replaces the type of mixing you do but instead it must be done BEFORE someone can do the type of mixing you do. Instead of treating necessary changes as constantly "fixing" or "improving" something in the mix, the changes become a list of necessary cues that are part of the bands presentation.
Think about which faders are under your fingers the most during the show. A DCA is not very useful if the gains within the DCA are not right.
Have you ever matched a recording by varying the effects during different parts of a song, say chorus and verse? How likely are you to do that if you are still chasing a bunch of channel faders for level? You were the one saying you liked to have 7-8 channels of effects. Many 10 fingers on the faders mixers couldn't even imagine using that many because they wouldn't want to lift their hands long enough to use that many effect channels.
I also remove all the effects on vocals during spoken parts between songs. I also duck or mute unused mics for each song. This is not set and forget mixing.
In order to get the type of mix you are talking about requires the person at FOH to be actively engaged with what the band is doing on stage, and I would say someone constantly chasing problems caused by poor gain structure are unable to be actively engaged.
The devil is in the details but those details are only about 5% of everything under our control. Having a solid foundation means not having to worry about the 95% and being able to focus on the details that push the presentation from good to great.
