[patrickrea]

I go through this everytime I leave and return Toronto harbour by the Eastern Gap. Sailboats, tour boats, regular power boats, freighters, jetskis and windsurfers come through a relatively narrow, but very deep channel. Wind direction changes every 10' if it's out the east or west.

Hoping that the other guy will give way assumes too many things.
A) Might not see you - unlikely as stated earlier the boom on a Nonsuch is quite high.
B) Has shoals of his own that he is dealing with - we are talking Southern Georgian Bay after all. It's a wonderful rockgarden as all the prop repair people will tell you. You said he has lots of water, but what you consider lots and what he considers lots are totally different.
C) He has other difficulties happening. Screaming wife/ child, rigging issues, his towed dinghy just flipped over. Trolling line out too far.
D) He's polite and alert. Which is way too much to hope for these days.

The best you can hope for is that he holds his course. You deal with the rest.