Thank you for this info I had no idea but makes perfect sense indeed. I have a cousin that he never takes his gen GMT Master2 out of his hand meaning that he showers with it frequently and he did not have any issue but now I read this maybe he is lucky
I tested my Noob PO in the watch smith's and it passed the 60meter reading with flying colors, his gear was limited to 60m so it might even went further, he had a bunch of gen Rolexes in the back and he told me that he tests all of them with the same vacuum chamber, this means the watch is really well made and suitable for swimming and some serious diving.. best thing to do is have the watch tested, even my smith gave the caseback half a turn since it was not properly screwed so it took his experience and tools to bring this sealed state so always pay him a visit if you want to use for swimming!
