What troubles me with all this...how can I tell with certainty what point of sail I am on with respect to the true wind at a given moment in time? On a beach cat with no electronic wind instrumentation to calculate true wind direction, I always have to guesstimate where true wind is before I can state "I'm broad or beam reaching".
It appears that he is asking how, on a fast boat, you can tell where the true wind is coming from when your sails are trimmed for the apparent wind.
The most obvious clue I can think of is the direction of the waves.
