LEE BOW EFFECT

One point he makes is true, pinching rarely helps, not even to just get the tide on the knock because it doesn't help what you're looking for. Which is an increased power supply by combining the true wind with the created tidal wind thus increasing the apparent wind on one tack. The water may well be moving over the bottom and away from the mark, but one of the boats on it will be moving faster over that water than the other simply down to the increase in wind - sure they'll have to tack, but where and when, becomes important. (the tide might be faster offshore than inshore, the wind might be less inshore than out to sea, the current very rarely is acting constantly over the entire course (you tell this by looking at the water).

Trust me, he's wrong.

We once sailed an entire windless race without pumping, up the Thames, entirely on the wind created by the currents movement against still air - that's the effect you're looking for, created tidal wind to combine with the true wind, think of it that way.. In that instance it was a favourable lee bow tide on both tacks, the guys that did better were those that spotted where the current was fastest (on the inside of the bends).

Many a day back home in a drifter, we sail home choosing the tack that puts the tide on the lee bow, those that don't just drift downtide. (You can't tell some folk)

I have heard both the tide thing and the issue of tacking just under another boats lee bow. 

 

I understood that the idea of tacking just under another boats lee bow was that it slowed them down enough either to make them tack off or enough so that after a short while you can then tack across them

 

That's different. If the tidal flow varies across the course, then obviously the wind shifts resulting from the tide will vary across the course, and a good (or even semi competent) navigator should take advantage of that - looking for the maximal tidal lifts, and minimising the knocks. 

If, however, the tide is even across the area of the course, then the lift you get on one tack (relative to the ground wind) will be offset by the knock you get on the other tack (again, relative to ground wind). What you gain on the swings, you lose on the roundabouts.