So what are you considering a super star again? High usage guy? What do you consider high usage? I can take a team full of 20-25% usage guys and win it all, but some of those guys are all-stars and potential hall of famers (most of Barkley's best seasons are 24-26%, and he was a bonafide super star). Yes, I can win without one 30%+ usage guy (majority of my rings are without one), but high usage isn't really the only defining aspect of a superstar.
No, you can't win if you don't have anybody over 17.5% usage on your squad, that's for sure.
Also, about your assumption regarding double teams: no.