This makes the bow tilt down a bit. I have a hard time with this. A few things to consider. Boats naturally tend to trim bow up with increasing speed. This becomes more pronounced on hard chine boats due to the dynamic lift at the bow and chine immersion.
Some boats increase resistance with bow down trim and some have reduced resistance.
So achieving bow down trim does not look like it would reduce resistance enough to permit great speed increases. I suspect this falls under the mythology category. So speeds of 7 mph for 12 hours might fall within the realm of possibility but 14 mph, even for short sprints strains credulity. Suppose we assumed that the boat planed. Then the horsepower required becomes 5.25 of total to sustain the speed and that assumes a boat designed to plane - something kayaks do not do well at all.