Hey bill, I really dig how you are also a mad keen experimenter.
I shoot tons of jet skiing video and other water sports up the river, so, here are few tips:
use a circular polariser
expose low if possible, I use -1ev
sharpnes set to 0 or what ever the minimum is on you camera - you can always butcher it up in post as desired
big, heavy, smooth tripod.
I use a Sachler FSB6 head on some HD Manfrotto CF legs, with a 10kg bag hanging
shutter speed: well... this is a comprimise (isnt it all...) If shooting 30fps, 60th sec will give you a nice smooth vid, but is not fast enough for action. 120th looks 'flicker' on a plasma TV or projector, but is ok on a LCD TV. but, the fast shutter speed makes for much better slow mo !
Fstop ? Look up the MTF charts for your lens http://www.photozone.de/all-tests
to find out what the sharpest F is and the best CA - most lenses is around F6 to F8
Less glass is usually better - ie, if you can get away with out the lens extender = better images.
and ... uhhh, bus stop