The thing about water resistance is that it is almost always a guess. It is an estimate, based on the watch being in ideal condition under controlled circumstances.

This is almost never the situation.

So, deliberate submersion of a watch into water is a gamble. It may be a small gamble, but it is a gamble nonetheless, so I do recommend it unless one really needs to be wearing the watch.

Why take unnecessary risks and wear a wet watch?

And remember: water resistance is based on batch tests most of the time.

understand Swiss quartz watches are preferred (to Japanese quartz) among people more knowledgeable about movements.

Preferred by whom? Japanese quartz is usually better. Swiss marketing has an intrinsic markup, so you can pay top dollar for a basic Swiss movement whereas for the same price you'd get something significantly better from Japanese companies (ie, compare a $400 Swiss quartz watch to a $400 Citizen Eco-Drive or a Bulova of the same price).

Swiss Movement means "made in China" most of the time, but marked up because some highly paid person was in its vicinity when it arrived in Switzerland for a brief casing.