When looking at boat listing, I see all of them list boat speed as cruising and max. Is this under power, or are they attempting to indicate under sail.
This is generally correct. Do be aware that most of the time they compute max speed based upon the simple water line formula. Almost any boat can exceed that when surfing, and some boats (high performance race boats) will certainly exceed their hull speed.Under power. Max speed under sail can be more, depending on the conditions.