So the study was, they asked people with testicular cancer if they smoke weed...
Seriously?
That means there's a link?
Just because somebody with testicular cancer smokes weed doesn't make it the cause, and just because a majority of people with testicular cancer smoke weed doesn't make it the cause. Lots of people smoke weed. This smells like a big nasty coincidence.
Maybe if they had somehow proven that someone without testicular cancer, developed it directly from marijuana use, it could be credible, but as it stands this study is a load of crap.