Tim, we are talking micro knots but we always want to be the best we can be when going after the dragon.
Years ago there was the dicussion about the micro bubbles that are formed and roll along the hull, a result of sanding. The latest that I have seen on Scuttlebutt is the same but it also said the smaller the boat (including model) the less the effect. On big boats polishing is felt to cause the water to stick to the hull with what drag that might cause.
For me, it has been to get the stuff off the hull left from drying, collisions and scrapes with concrete, poles and even barnacles like on the channel bouys at Mystic. Man they cut deep into the gelcoat.
I wipe the hull on the flat of the hand with wet 1500 grit then finish with water and cleaner on a rag.
Not a scientific answer but it makes me feel better.
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