Jay,
I was filming on NOMAD in 2006 at Bugatti on the way to Marion.
The tides were lead up to the new moon.
In some places, with the engines knocked in REVERSE, we were STILL doing 9kn over ground........the current is amazing.
Funny though, it made looking for the better GT spots easier since the bait would just sit on the corners out of the flow.
I'd go around either new or full, as Jon said with a peak during the day to maximise the run of the tides
Aaron.