At the risk of slings and arrows . . . and with genuine humility, as I am not an expert by any means, I will (just once) try to explain my recommendation.
First, it hits over 80 degrees daily almost all year round here in Honolulu and I don’t have A/C in my house or even fans in my growing areas.
I switched to 100% RO water at the end of August last year. I hand water, almost daily for phrags, with water that runs about 4-10 tds. I try to fertilize once a week, with the help of my CFO (chief fertilizing officer) hubby, but we are both still working and that is aspirational. So, I toss a small number of time-release fertilizer nuggets and a sprinkle of dolomite into my pots when I repot and hope for the best. The positive difference since RO is astonishing - for me. There is a good article about water posted about 30 days ago at orchids.org by Roy Tokunaga, who is the most studious orchid grower I know.
Amost all of my phrags. in less than 4-in pots (think hundreds) are in pure NZ sphagnum moss. All of my phrags are in clay pots. I have grown many larger ones in sphagnum, and they have done ok, but I am moving most of the bigger ones to a different media (skipping explanation).
Yet, I currently have at least 3 young besseae flavums in spike (I can post pics in a few days) and have also bloomed the red form ok, although I have lost more than a few (all my besseaes were grown from flask).
I have definitely seen the heat stress, but when a plant crashes like Brucher’s, I have observed that the roots are generally suboptimal. So, I suggested checking the roots. If (and only if) they look bad, sphagnum is amazing for getting good roots going (think S.A. flasklings with no roots at all). Below I have a neglected (and over-exposed) seedling I repotted out of its 2.25 in pot last night (deflasked late 9/18, put in the 2.25 in 12/18).
Sphagnum also has mildly antiseptic properties and a plant like Brucher’s seems vulnerable to me. Plus, if kept moist, particularly in a clay pot, I believe the sphagnum helps keep the plant cool. I’ve tried the LECA, with bad results, usually after about a year. I am experimenting with the Grodan cubes, but do not have enough experience yet to comment, except that they seem to be keeping my little kovachiis alive (on par with or better than the sphagnum; time will tell).
While I would normally agree with Eric about pulling off (rather than trimming) the browning leaves, I suggested cutting because most of Brucher’s leaves looked affected and the plant needs at least some of its solar panels to work.
Finally, I suggested laying out bare root for a few day, with “clean” misting, in a cool shady spot for sure, to try to get a growth cycle going again.
Ok, if you read this far, my sincere apologies. Each one of you have great ideas, which is partly why I enjoy this site (plus your beautiful plants and photography of course). My best (perhaps only) advice is to but lots of orchids, to ease the pain . . . Best, Kate
P.S. to Brucher - when you said you were taking the matter under advisement, I laughed and checked my work email.