Tolkien, on 08 January 2013 - 10:51 AM, said:
Post hoc ergo propter hoc. I think it's much more likely that usage of ECM is indicative either of premades or of a good, experienced, minmaxing, elite or whatever you want to call it, player. So your numbers aren't really showing the impact of ECM itself. Of course you cannot get the data to sort out which is which but it isn't clear if you are putting the blame squarely on ECM rather than other factors that correlate with ECM-usage.
tl;dr Why aren't you mentioning confounding factors?