The problem is that, by random chance, some players will be more successful than the norm, while some will be much less successful, even if the game itself is totaly random, with no skill element. So, just the fact that some players win while other lose, doesn't really mean anything. You would need a very large sample, tracking players over the long term, the very long term, to be able to prove that there is a meaningful skill element. Personally, I believe the 'long term' in tbj is probably something like 1,000 tournaments, to start getting meaningful results. Doubt if we could find enough players to get a really meaningful sample at that level, for a statistical analysis.