15 metre mark

[shuumai]

So, do the you, the people of this forum, practise staying under for up to 15m (16.4y)? If so, do you do it during events that are 200-400m?

During breaststroke, is it practical to stay under for 15m since constant kicking isn't allowed?

I still can't believe the underwater limit isn't shorter in a shorter pool. I mean, 15m is 60% of 25m and 65.6% of 25y.