No one said that US wasn't any good, just that during those years the competition was not that crazy in the mixed scene. The first time US fought against a super team was Mother's first win. I don't think US used their best players though. Mother kept winning, until US brought in their new trump card and won that tournament. Deity beats Mother. After that, the mixed scene started declining again, you see this with SLX's 2-0 choke against northern sign. Alumni starts creating a team, and then more super teams spring up. Alumni wouldn't lose, so a lot of them ended up disappearing.

I'm sure that the idev tournaments have always been competitive. No one said idev US didn't face good teams, just that the overall best GST in terms of stacked teams was summer 14'
Could have easily been the one before that too