Reducing the RMSE isn't quite that simple. Teams have been working for years to improve the algorithm by 10%. You can't just "boost it up" in order to win. It takes serious work. BPC is still working to improve their algorithm like everyone else but questioning whether they "expected this to happen" is ridiculous. None of the top teams "deserve to lose", they've all done great work and deserve a round of applause, regardless if they are the ultimate winner.