Here's the kind of test that doesn't cut it. It's for the hydrophilic coating, Hyspeedkote. The results look interesting. Interesting enough to include in a test, but there are too many uncontrolled unknowns in real-world testing. This is what it takes for a thorough, objective test. A controlled environment, a carriage that can maintain a set speed and electronics to measure small differences in forces.

BTW, that's me on the plank. Seriously, $100k and a week at that tank and the answer is known.

Would a hydrophilic coating make the boat sit lower in the water?