[raxxorraxor]

I believe a good measure that you have enough confidence is indeed when you have no problem with asking stupid or obvious questions. If someone judges you for that let them reiterate problem and alleged solution. They are able to do that perfectly then and onus is on them in that case.

It is too costly if people are afraid to speak up in meetings since problems get hidden and remain unsolved. Even with tight deadlines everyone has these two minutes.