H.P. White is considered the best after market independent testing laboratory in the US. There is one thing I did notice they did not mention Bergara barrels which I believe would test on a level with TC and Knight. The rest is commonly known to gunsmiths that specialize in muzzle loaders so it is nothing new. I also suspect that they probably looked over a hundred or so and picked out the worst ones.
To give credit where it is due; I must say that there designing and the quality control on the top of the line guns has steadily improved over the past 10 years and if they kept it up for 10 or 15 more they might reach the quality consistency of TC of course the price will change accordingly.