Another interpretation: Try to figure out which side has more intelligent defenders and control for that when evaluating arguments. (On the other hand, the fact that all the smart people seem to believe X should probably be seen as evidence too...)

Yes, argument screens off authority, but that assumes that you're in a universe where it's possible to know everything and think of everything, I suspect. If one side is much more creative about coming up with clever arguments in support of itself (much better than you), who should you believe if the clever side also has all the best arguments?