LogFAQs > #971571875

Singles format in the main game is a huge reason why Smogon rules were popularized, because it's what everyone knew and used. 6v6 singles with Smogon rules is what I learned in gen 4, and when I entered VGC 2010 I swear the sheet of paper I filled out for my team was a singles format team build. I hated doubles, I still don't like doubles, but official tournaments adopted doubles for every gen after that so I never bothered learning it.

Battle Tower has a doubles format and I'm pretty sure that's what tournament organizers want you to use to practice (as opposed to Showdown). Did you know that in 2008, South Korea held official tournaments where you had to prove your Battle Tower Doubles Format record in the timeframe they alloted? I learned that last month when researching something.