P: Slow UI when using Mac and Custom Display Profile

Sadly, your answer encapsulates the problem to perfection.

Andrew, the main problem on this thread is not Adobe, it is not the bug, it is not the time to fix it, the main problem is you.
With your permanent contempt, your decision to become a blind advocate for Adobe, Adobe who does not need you at all in this situation and may terminate all your contracts after some phone calls to Adobe top management, and your full ignorance of software development.

OK fine, let's come up with a false narrative that makes you feel better:

Once upon a time.... .... Adobe deliberately released this bug, knowing full well it would cause issues for a small but vocal group. Then, they dragged their feet on purpose in fixing it, because again, they want to upset a certain group of customers. But that rare group gathered on one Adobe forum and screamed bloody murder. They threatened and purchased competitors software (that will show the evil empire). 

Now back to reality. 

And for that reason Rodney, you're fired.

I'm not an apprentice Belinda Trump <g> 

Sadly, your answer encapsulates the problem to perfection.

Indifference, snarkiness and arrogance in equal measure.

In my business, an employee displaying these traits doesn't make it to the end of the day.

And businesses displaying this attitude to their customers are unconsciously handing their bread and butter to the competition.

Just imagine a waiter, a doctor or car mechanic giving you an answer like that? 

And for that reason Rodney, you're fired.

Yes, I imagine that a post made three months ago constitutes excellence in business communications and customer care; there is nothing new to report other than the issue has been detected and a fix is coming. 

So I'm OK using V9 for the time being.

Good for you. A fix is coming and “Patience is a virtue.” That is the facts and the point. 
There will be no wine or bug fix before it's time. 

Rodney, if you imagine that a post made three months ago constitutes excellence in business communications and customer care, you are as out of touch with best practice as Adobe.

I did, in fact, have the 'self control' to back up my older catalogues - a practice founded on hard experience of previous Adobe fiascos. So I'm OK using V9 for the time being.

But that's not the point is it?

We are not all in a production environment and we are not even all experienced users, so taking cheap shots at those in difficulty for not being clever enough to foresee Adobe's release of defective software is not all that endearing.

The average user shouldn't have to build a protective firewall before updating software to preempt sloppy implementation by its vendor.

Rodney, I have to say that three months seems an awfully long time for this issue to be ongoing, with no apparent progress and little communication from Adobe.

in my case, the problem with Lightroom went well beyond slow to a total lockup of the machine that required a hard reboot. After some time with Apple and Adobe tech support, I found that I could get passably slow performance by turning off GPU acceleration and using AdobeRGB color space. Since a) one of the calibrations of my Eizo monitor is AdobeRGB, b) I expected the wait time for a fix to something so fundamental to a professional workflow would be...well, less than it has been, and c) the program was usable with those mods, I opted not to downgrade.

But, as a result of sub-optimal performance in Lightroom, I’ve been turning to Capture One more and more. I’ve always liked its color interface, but thought it’s catalog was sub-optimal. Now, being able to scroll through a catalog of image files makes it altogether more pleasant than using Lightroom.

I’m sure that in the universe of LR users, I’m in a small minority, but it can’t be good for Adobe’s business for this to be going on for so long with so few updates from them. 

What you haven't grasped is the fact that Adobe's handling of the issue is a case study in poor communication and dismal customer relations.

Only for those who refuse to read the post made here, three months ago by Adobe. Hint; it's the second answer in this long slog of pages. 

Not to mention the self evident absence of quality control.

And the self control to back up older catalogs and data, test a new build and find, within minutes of use IF (big if) the bug affects you, to roll back. 

You'd think some here, (who state they are in production environments) would know this for any mission critical software, would have attempted. 

The whole world and its (digital) dog has grasped that, bill_.

What you haven't grasped is the fact that Adobe's handling of the issue is a case study in poor communication and dismal customer relations.

Not to mention the self evident absence of quality control.

You fall to grasp that Adobe has accepted this as a problem and that they are working on it.