The Circle of Confusion comes from Floyd Toole and Sean Olive - you heard of them?
For sure. But i'd say that this CoC tells us more about making new records in some genre sounding more or less close to familiar and commercially successfull ones. Even if some sound engineer personally prefer some another sound and find resulting mix/master suboptimal from ultimate fidelity point of view.
Very improbable that really competent and experienced sound engineer will constantly sincerely and ignorantly make wrong decisions that will lead to great tracks.
It's more like "movie presentation". Directors, producers and editors will make movie pictures according their creative vision and public common sense, but they will do it concsiously and with properly calibrated monitors. I think that barely any movie studio will release depressive noir or dark thriller colored like teenage comedy just due to wrong ICC profile applied.
For some example, we can just read something about Bob Katz's Studio A.
All five speakers are augmented with two subwoofers–JL Audio 12″ Fathom F112 subwoofers crossed over with a steep linear phase Neville Thiele Crossover. The mating of satellites and subs is seamless and perfectly calibrated by use of Acourate loudspeaker and room correction software from AudioVero. Acourate corrects phase, impulse response and time alignment. Response is +/- 1 dB to a target from 17 Hz to 20 kHz.
Good sound engineer must know sound of real instruments and all frequency bands and I hope he never "just come into some assembled studio and try to make some mix sound right". Otherwise all the chanses of keeping sound "realistic" is kind of lottery, and we still see a lot of classic/acoustic albums with consistently "correct" sound.
Anyway,it might be just my opinion, but I feel better if some actions done have some rational reasons behind them. Even if it's greed, lazyness, cruelty but not just ignorance, because fight with ignorant solutions is futile and unpredictable.
Top B&W speakers is absolutely reasonable solution for british studio, because they have low distortion, very well engineered, can withstand a lot of power applied and can be repaired locally if needed. Question about sound at LP is still open, and. unfortunately, I don't have any access for Abbey Road staff.
Take a look at all the B&W loudspeakers they use in the mastering rooms at Abbey Road Studios. Be sure and contact them to tell them how "ignorant" and "inexcusable" (your words) are, and perhaps you can teach them how to properly set up their studio.
Loudspeakers is just one part of the puzzle. Then you have source, amplification, room, equalisation and current SPL at listening point. Only then you'll have some audial experience transfer function that must be kept in mind while you apply some changes to track.
Easiest example is Fletcher-Munson curve - if you don't really know how loud this track is playing now and how loud it will be reproduced (i.e. is it intended for FM radio, for home hifi or for dance floor) you can't really decide, if you need to add some lows or not.
1) Since B&W's are often used in mastering studios, and adjustments are made to the recording based on the curves and "tonality" of B&W speakers, there is definitely merit to using B&W speakers at home to attempt to reproduce what the recording engineer intended.
Returning to previous point, I'd say that one shall not substitute 802Ds + Bryston ( and possible tri-amping) in treated control room with some entry level BWs + same class receiver in domestic room just due to typical on-axis tonality of brand. Even if 802Ds are not equalised to some other curve, which is still unknown for me.