I'm new to this, so forgive me - I thought there was some extra risk to the watch involved with having the seals in a watch degrade, past the false sense of security you would have getting the watch wet. But that doesn't seem to be the case.
No probs! The silicone grease used on the rubber gaskets of a watch caseback and crown to seal them won't harm the gaskets, and it should prevent water getting in. However, it needs to be done by someone who's competent, and the watch needs to be tested to ensure these and the crystal are fully sealed.
My reluctance to expose my own watches to water is because a) I don't have the kit to test my watches, b) I couldn't be bothered with sending or taking them to someone to do it, and most relevant point of all, c) I can barely swim, so the weight of a watch is likely to drag me down to the ocean floor, where I would discover that the water pressure was too high and the last thing I'd see as I drowned was my watch filling up with water - which would annoy me more than the drowning.
