Pleated leaves can also be the result of too much watering! If you don't know what is causing this, take the orchid out of the pot and check the roots. If your roots are brown you need to trim them off and transplant using new potting bark. Stop watering them often.

Here is a link that might be useful: Orchid Diseases

I didn't see anything in your link that mentioned pleated leaves. The brassia and odontioda are watered twice a week, while the others get it once a week, and of course I check the wooden skewers to make sure they're dry or almost dry. The orchids are all in clear plastic pots so the roots are visible. I've never read or heard that pleated leaves are caused by too much water.

I took Jessica's advice and unpotted the brassia, which is one of the few orchids I have in a clay pot. There are tons of healthy roots, no rotted ones that I could see. Here are a couple photos showing the roots and pleated leaves.
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It is lack of moisture. I don't have any Odon's but all of my Brassia I grow moist and never let them totally dry out. If you are going to use large bark you might consider adding chopped sphag.

Brooke

Thanks for the tip, Brooke. I have some sphag somewhere. It's good to know that I haven't been overwatering. As I mentioned, the brassia never fails to bloom, usually 2 spikes at once and sometimes twice in a year. That's amazing for VT. However, the odontioda seems stalled. I'll give it some sphag too.

also, I find that my odontioda's leaves twist themselves and pleat a bit lengthways but was always told that this was a ploidy issue, just if someone has the same sort of concern.

What's a "ploidy issue"?

"Ploidy issue" is saying that perhaps a plant has extra sets of Chromosomes that cause abnormal growth in the leaves or even abnormal flowers.
Most orchids are 2n where one set of chromsomes comes from the pod parent and the other set from the pollen parent.
Where there are extra sets of Chromosomes eg 3n, 4n, 5n ......sometimes the flowers are superior.
Possibly an issue with some orchids in the foliage Department but the cause of pleated leaves is much more likely to be lack of moisture described by Brooke in the post above.