Performance Enhancing Bugs

IMO, there always lies another bug behind one performance enhancing bug. The bug behind scene maybe in code, or it is just the assumptions you made when writing the code. e.g. ScalarBot’s gun is using far smaller cluster size nearly randomly (actually, it depends on the structure of the tree, which is not consistent over battles) in the past, but that bug helps against surfers dramatically. That bug is performance enhancing because the assumptions I made before using kNN with huge cluster size breaks when facing surfers. And using smaller cluster size is generally a rule-of-thumb of Anti-Surfer Guns.

Agreed. And from the rumble score, it seems that the rumble thinks re-introducing the bug didn't actually change anything, which means that it might be something else. Melee wavesuffering is so much worse than 1v1...