Michiel
actually there is detailed algorithm described in tournament header.
Your tiebreaker score is calculated as average percentage of winning scores You achieved.
So 2nd player who scored, on average, 90% points will be graded higher than 2nd player who scored 80% points.
Look in tournament description - I think it's good, has examples and describes additional details if You are interested (in description above I skipped small print for clarity, but if You want to actually calculate Your score - or other player's - You will need it).
