Dubious
The unit of measure in the table is MPH not kts and the surface response to terricloth described in the CAFE report is EXTREME. The note at the end of the article on the effect of surface polish as a source of error in precise performance measurement is interesting. Mind you I have never seen a boundary layer but I believe the low speed air immediately adjacent to the surface is there. If there is a difference in a test I would expect it has something to do with the boundary layer attachment rather than what you put on the surface. In the CAFE test flying two planes at the two times with identical recordings would be more meaningful. The second test specimen with no change between flights. I wax my plane and I have never seen any change in performance as a result. If I could pick up 2.5 kts or 2.5 mph with some surface treatment process I would be strongly inclined to do it. I believe you would not see that kind of difference on a well maintained airplane. I will wait and see.
Bob Axsom