Awesome John! I'm sure there's a huge list of "don't ever do this on a raceboat" items... Here are a couple I've been yelled at for...
1. Don't wear shoes that put marks all over the gleamy white decking.
2. If it's light air, walk VERY softly as the stomping around makes vibrations in the hull and you lose .00000551 knots of speed which will make the skipper grimace and most likely shout at you.
3. Don't drop anything in the water, especially yourself. Not because he/she's concerned about your safety but because a man overboard is essentially forfeiting the race... Anything dropped in the water off of a true racing sailboat is likely worth more money than your soul... so mind those winch handles
and finally....
4. If the skipper asks you for a beer... be swift about it
I'm sure there's a thousand more
