From: WaIIy

Also, it's good form to pass behind, not across the bow of a sailboat.

True which is my usual method of passing a sailboat whether under power or
sail. In my boating years I have found that most sailors (sailboats) are polite
and most wave back when I wave to them.

To each their own. I don't have the patience to be a sailboater I like to get
where I am going relatively quickly.