Sorry for being late to the party, but with the holidays and work and family, the past few weeks have been hectic. This morning I have thouroughly enjoyed just browsing the internet again. This was an interesting thread, and I enjoyed all 10 pages of it. I hope I'm not picking at a healed-over scab, but I'm in a good mood and want to give one more data point on the discussion...
When I read the title "Tides and Forward Progress" and then the first sentance "From another thread Marin's friends seem to think one's progress as affected by tidal currents does not average out. ", my first reaction was "of course, I see that every day".... and then I watched the argument erupt, and was fascinated by all the directions it went in.
From my boating experience, I've never had tides even out.
I grew up in Hawaii where the current is nearly always East->West (it sits on the bottom of the North Pacific Gyre), so even as a 15 year old in a kayak I always headed east first, so that the current (and more importantly trade winds) would blow me back home when I was tired at the end of the day.
Then I moved to the Seattle area, and moor my boat in Tacoma. Vashon Island sits just a few miles off my marina:
I have "known" for some time now that the currents are always moving in a clockwise direction around the island. Now, I readily admit that may be a bit of an exaggeration, but personal experience has taught me that any time I am heading to destinations north (which is still Puget Sound destinations for us), it is worth the extra few miles to get to the west side of the island in order to head up Colvos Passage.
But these are just localized nuggets of information, and I am not a long-range cruiser so it has a dramatic impact on my 5 or 6 hour travel times. But those boats that are travelling much further than Seattle from my marina would be relatively unaffected by the current around the island -- and it would, in essence, "even out" across their trip.
At least, in theory.