Jon, I just read the same thing on CN. I took your advice and cleaned the miniscule amount of vaseline that was on the threads of the EP. I barely put any on, I would *NEVER* slop that stuff all over the EP
The eyecup now turns like it did before and after wiping the vasoline off, there isn't enough there now for it to run or seep anywhere, in fact it is 99% gone from all the wiping on both the eyepiece threads and the aluminum piece with my fingernail and some soft paper towels,(very carefully of course). I *NEVER* leave my eyepieces in a hot car or even in a hot house for that matter. I do 95% of my observing from my yard, and we have the air conditioner on all the time when it is hot in the house.
I also want to mention that when I *DO* borrow eyepieces from club members, I treat them as "theirs" with utmost care, and not "tamper" with them.
I want to thank you for the advice however, it is always great to learn new things that may be bad for equipment.