That is completely false, I know for a fact a 5 time world champion has a button barrel on his rifle as I type this and he's told me he prefers a button barrel over cut if its a good button barrel.If they were superior methods of rifling why do all of the top long range shooters that I know use cut rifling?
A good barrel is a good barrel.
Also I know he took a Bartlien off and replaced it with the button barrel he currently has on his rifle after testing them side by side.
There more button barrels out there competing than you think