here's a note from Alonzo:
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Good question. I told David that the course will take 4 days but did not
mention that some time it takes 6 days. I can do an Open Water Course in 3
days if the weather is in great conditions and the person is very good
student and good in the water. I think that 4 days 6 to 8 hours a day is
just enough for a person to learn how to be a great diver and I will help
them acomplish that.

Regards
Alonzo