For example, in a game of "StarCraft II," if you're playing as the Terrans and your teammate is playing as the Zerg, and you keep your population growth rate low while your teammate keeps population growth rate high, your chances of winning are over 70 percent.
These 'researchers' understand very little about the actual game. 'Population growth rates' gimme a break.
Creating a statistic with so many hidden variables makes for a very useless statistic. Now if they were to give a set of simplifying assumptions that could be used as a basis for their claims, that would make it more useful. E.g., in a professional game in TvZ doing fast reaper harass leads to victory N% of the time given that the zerg player goes for fast expand etc. etc. This statistic may vary for several levels of player skill, since obviously fast reaper harass is easy to screw up, especially for new players.