The statistician in me is severely troubled by a conclusion like "statistical relationship" when the conclusion is drawn from studying just 3 (three) projects.

The statistician in me is severely troubled by a conclusion like "statistical relationship" when the conclusion is drawn from studying just 3 (three) projects. At worst case this means studying programming habits of just 3 (three) developers (appended: actually, 1 dev is the worst case). You just can't make any significant conclusions on such basis that generalize on whole population. Even if it was huge projects with hundreds of devs, you still can't make generalizable conclusions, because habits of all this devs are clearly not independent.