Can one go swimming with a Grommet?

One can go swimming after grommet but it is advisable to use a cap / ear plugs as a precaution. Though the conventional teaching was that swimming is not allowed but scientifically the size of the grommet hole is too small to allow a drop of water to enter. So, after 3 weeks, swimming should be allowed, but not underwater swimming or diving, wherein water may enter under pressure.