"What is not appropriate is to attach the power of the Keys to the laity outside of the apostolic succession, as such transfer is not described in the Scripture and was never taught by the Church."
Where is the "transfer" of the Keys (Matt. 16) from Peter to anyone else, authorized in scripture?
Where does it say that the disciples, what ever the number, had the authority to pass this gift concerning remittance of sin on to any other?
The gift is properly to forgive sins in the name of Christ, Who alone atoned for them.
2 Then the twelve calling together the multitude of the disciples, said: It is not reason that we should leave the word of God, and serve tables. 3 Wherefore, brethren, look ye out among you seven men of good reputation, full of the Holy Ghost and wisdom, whom we may appoint over this business. 4 But we will give ourselves continually to prayer, and to the ministry of the word. 5 And the saying was liked by all the multitude. And they chose Stephen, a man full of faith, and of the Holy Ghost, and Philip, and Prochorus, and Nicanor, and Timon, and Parmenas, and Nicolas, a proselyte of Antioch. 6 These they set before the apostles; and they praying, imposed hands upon them. 7 And the word of the Lord increased; and the number of the disciples was multiplied in Jerusalem exceedingly: a great multitude also of the priests obeyed the faith.From these we see how the power flowed through imposition of hands to many newly ordained priests. Their powers included, in addition to serving other sacraments, also the power of justice and condemnation.(Acts 6)
2 And as they were ministering to the Lord, and fasting, the Holy Ghost said to them: Separate me Saul and Barnabas, for the work whereunto I have taken them. 3 Then they, fasting and praying, and imposing their hands upon them, sent them away.
(Acts 13)
15 For if you have ten thousand instructors in Christ, yet not many fathers. For in Christ Jesus, by the gospel, I have begotten you. 16 Wherefore I beseech you, be ye followers of me, as I also am of Christ. 17 For this cause have I sent to you Timothy, who is my dearest son and faithful in the Lord; who will put you in mind of my ways, which are in Christ Jesus; as I teach every where in every church.
(1 Corinthians 4)
5 Not that we are sufficient to think any thing of ourselves, as of ourselves: but our sufficiency is from God. 6 Who also hath made us fit ministers of the new testament, not in the letter, but in the spirit. For the letter killeth, but the spirit quickeneth. [...] 9 For if the ministration of condemnation be glory, much more the ministration of justice aboundeth in glory.
(2 Corinthians 3)
13 Till I come, attend unto reading, to exhortation, and to doctrine. 14 Neglect not the grace that is in thee, which was given thee by prophesy, with imposition of the hands of the priesthood.
(1 Timothy 4)
6 For which cause I admonish thee, that thou stir up the grace of God which is in thee, by the imposition of my hands. 7 For God hath not given us the spirit of fear: but of power, and of love, and of sobriety.
(2 Timothy 1)
Was the power of absolving sin somehow not transferred? There us no record that the imposition of hands transferred the power partially; moreover, administration of condemnation and justice would not be possible without an ability to absolve sin, as well as condemn of it.
The James passage deals with confessing to one another but there is no mention of absolution.
Here it is.
18 But all things are of God, who hath reconciled us to himself by Christ; and hath given to us the ministry of reconciliation. 19 For God indeed was in Christ, reconciling the world to himself, not imputing to them their sins; and he hath placed in us the word of reconciliation. 20 For Christ therefore we are ambassadors, God as it were exhorting by us. For Christ, we beseech you, be reconciled to God.(2 Corinthians 5)
10 And to whom you have pardoned any thing, I also. For, what I have pardoned, if I have pardoned any thing, for your sakes have I done it in the person of Christ.
(2 Corinthians 2)
Where is the "transfer" of the Keys (Matt. 16) from Peter to anyone else
Never happened. The office of Peter holds the keys, even as it commissions bishops and priests to do the work of Christ, as described above. At the same time, the office of Peter did not die with Peter:
13 But I think it meet as long as I am in this tabernacle, to stir you up by putting you in remembrance. 14 Being assured that the laying away of this my tabernacle is at hand, according as our Lord Jesus Christ also hath signified to me. 15 And I will endeavour, that you frequently have after my decease, whereby you may keep a memory of these things.(2 Peter 1)