Don Johnson

“binding and loosing” are rabbinic terms for forbidding and permitting, that is, deciding things, so I see this giving of authority by Jesus to the disciples as directly relevant.  Jesus had 3+ years of ministry, not everything was discussed that needed to be discussed and decisions were made later and God is backing them up with this.
Jews were familiar with the Great Sanhedrin and local sanhedrins deciding things.

The NT was written under the supervision of the apostles, so I do not want to abandon my claim that as a group they did not make mistakes.  Individuals yes, as a group, no.
I can agree that Paul is everything he wrote he was, but I do not see that he was the 12th apostle as he never wrote that he was. the 12th apostle. 
I also do not see any hint that what the 11 decided was considered wrong.  What they did is what we do today, they referenced Scripture and prayed about it and decided to act.  And there is no indication of error on their part, displeasure of God, etc.  This is exactly what we do today when we act in faith.