That sums it up. In spite of the failings of the "Peters", Jesus knew our failings and still selected men to transmit His teachings. I'll accept the guarantee of Jesus that He is with the Church to teach His truths in spite of our weaknesses in following them.
Peter was weak, and a bit slow. I could not have a faith based on his faith. Still, if HE was not worthy, where does that leave me?
I do think that the Vatican did grave harm to the faith by pushing so hard against the Iraq war. (Truthfully, the Pope NEVER explicitly said that the Iraq war was wrong... it was the Curia which persistently misstated him. Yet, the Pope is responsible for them.) Whenever Church leaders speak outside their purview, they weaken their moral authority on the issues which they do have authority on.
The Pope speaks infallible doctrine on matters such as abortion and abstinence. He speaks authoritatively on matters such as birth control, and homosexuality, and anyone who challenges that authority would have to the impossible task of creating valid grounds to challenge it on. He offers mere opinion on issues such as the death penalty and the Iraq war.