Yes I'd be annoyed too. But you hadn't explained this so I had no idea of how the faux pas transpired. Jimmy's reliance on John's was the mistake. With Jimmy's vast experience it's hard to understand his slip-up this time.
I realize how speakers and rooms have such variations in sound and would think the best rooms would have multiple speaker set ups and possibly moveable walls etc. to soften or harshen the rooms acoustics. I know most studios have little flat toned speakers (Auratone) to switch between to hear how the mix will sound on less dynamic systems and even a small radio. Of all the LZ albums, I believe II has the best soundmix. If I were Jimmy, I would have used the studio/studios he used to mix that album. Personally, I think the masterpiece PG has a tinny sound. It doesn't have the ummph of II. None of the other albums do to me, including IV.