I’d wager, the seal is mechanical, made by a machine. And while not 100% sealed, meaning air and liquid proof, the inside is certainly more insulated from basic reclaim vapor. If the cap were 100% sealed, I doubt Dynavap would have posted the video on their YouTube channel on “How to soak the cap”. Using that information I devised my own technique, posted in this thread if I recall. I think I did it twice, just to prove they still work, after a long dry out period, not because I felt the cap was not performing properly.
The problem with this whole premise, is how difficult it would be to prove if there is any difference. To prove it to oneself, mark a cap that you NEVER soak clean, keep a record of your subjective results, the time period would be dependent on how often you use that one cap. In my case, it would be a long time, as I rotate devices, as well as many different DV’s & caps. At whatever point you believe the cap is not performing the way it did when new, you do a SOAK CLEAN. If you are HAPPY, end of experiment.
Personally, I wouldn’t bother, I have far too many things to test, that I prioritize way over a DV debate on something I don’t consider a performance issue. Even for me, I think this crosses the OCD line, but whatever makes a person happy and satisfied is the correct answer for that individual.
Now how much time have I wasted writing this……