Why would a local Bishop preside in the presence of the supreme Pope? I doubt it works like that today. :) That doesn't logically follow.
God renamed many people in scriptures without ever giving them papal authority. The keys are a basic scriptural difference of interpretation we have. The mention of prayer at the Last Supper was to encourage Peter after he would betray Jesus. It was not a conveyance of authority. The "feed my lambs" discourse was the mirror of the betrayal. The point was to show Peter what he had done.
If the Keys of the Kingdom of Heaven are not the gospel (the means by which we are saved - the door to heaven opened to us) what are they?
I, frankly, don't know how it would work today, but what if today the Pope would preside? No questions many things changed around the papacy through its 2,000 years of history. You cannot dispute that the entire issue was driven by St. Peter converting the first Gentiles, St. Peter having the vision that lead the Church do lift the dietetic restrictions; and it is St. Peter who makes the decisive speech, following which "all the multitude held their peace". St. James merely dictates the consensus that St. Peter had formed.
God renamed many people in scriptures
In fact, Abraham together with his wife, and Jacob were renamed, the father of monotheism and the father of the Jewish nation. This puts St. Peter in a very exceptional company.
The keys are a basic scriptural difference of interpretation we have.
You simply do not have an interpretation. The Hedelberg confession is plain absurd. If the keys are "preaching of the holy gospel" where is that interperetation suggested in the Scripture? Peter is not even among the evangelists. The Church and St. Peter are mentioned in the passage; the scripture is not. The Heidelberg confession is a wholy unscriptural set of musings that doesn't even attempt to link the interpretation to the actual gospel text.
The mention of prayer at the Last Supper was to encourage Peter after he would betray Jesus. It was not a conveyance of authority
"Thou, being once converted, confirm thy brethren" (Luke 22:32) says that Peter will lead the apostles. One who confirms others has the authority to confirm, it seems to me.
The "feed my lambs" discourse was the mirror of the betrayal.
That is was: it restored Peter's primacy. If, following the repeated confession of love, Christ wanted to "encourage" Peter, He would not have put him up for anoyher task of feeding ang guiding the "lambs", that is, the apostles and the rest of the Church (cf Luke 10:3).