Lol...Just read the study...
Just to remind everyone that correlation does not imply causality.
What the study proves is that people who do suffer from premature ejaculation usually do so because they have high levels of serotonin, which also causes quick reflexes. It also causes you to be happy, and not depressed, amongst other things.
Study does not, however, prove what most people are extrapolating: That quick reflexes = premature ejaculation.
In other words, it's entirely possible for people to be good in bed, and in FPS, and it's entirely possible for you to just suck at both. So if you suck at FPSs, it doesn't mean you will be good in bed...at all... It just means you suck at FPSs.