Phil Lesh101: I'd like to preface this by saying I know sometimes context gets lost online, so for clarity I wasn't trying to sound like a know-it-all or talk down to you. My apologies if it came off that way; it was (and is) certainly not intended. I was just making the point that even with the best intentions of making a band sound *exactly the same* night after night, even within the same venue, it can be pretty difficult. When it is differing venues it's even harder. As Rusty said, even with the more averaged sound offered from line-array systems, it's still very much dependent upon where you happen to be in relation to the PA system. As for the actual mix, that's a whole other can of worms
I do think you're right about the plug & play aspect of it. I noticed for the NYE shows they seemed to be using an AVID SC48 console. It was front and center in FOHland. I'm not sure if it was used as the main FOH board, or feed the Web/Recording streams, or all of the above. Derek didn't really seem very hands-on with it; most of the show he seemed to be just "enduring". I also noticed what appeared to be the older Dead/Ultra-modified Gamble EX FOH board from way back parked sideways in FOHland. Not sure what (if anything) that was used for. The SC48 certainly caters to the set-and-forget mentality as just about every facet of a show can be automated after the first run-through. I think if anything this highlights the different personalities and approaches to sound held by Healy vs. Featherstone. Don't get me wrong, I've seen plenty of Primus shows back in the day, but I've never credited them with achieving stellar live sound. Derek is just a different generation of sound, charged with meeting an entirely different set of priorities and deliverables.
I think the Grateful Dead proved themselves by providing a unique and rewarding concert experience (from visual to auditory) which in turn gained them a very loyal and dedicated following leading to sold out shows and record-breaking tour income, year after year; they took a pretty long-view. Modern bands/tours take nearly the opposite approach. They provide cookie-cutter shows streamlined to cut expenses and maximize profits at every opportunity. These days tours make money by putting asses in seats; more asses seated equals more profit. Thus they won't even consider using extravagant sound systems which might obscure sight-lines or waste rows of potential seating, and they don't "waste" money on crew or sound systems because they have a short view; next month there will be a new artist charting and a new tour. Unfortunately the demise of the Grateful Dead has left the remaining members without the "authority" to really "own their show" the way the band used to. It's also left the live sound industry with few acts really pushing the envelope of audiophile-quality live sound.