In the mythicist reconstruction of Christian origins, the risen Christ is analagous to the Angel Moroni in Mormonism and Peter is analogous to Joseph Smith as the first person to experience a revelation of the heavenly being. Smith figured out at a fairly early point, however, that being first in line wasn't sufficient to maintain control of the movement when everyone claimed to be receiving divine revelations. Smith found it necessary to proclaim himself the supreme revelator in order to make everyone else's revelations subordinate to his. He was able to do this by virtue of being the recipient of the Golden Plates and the seer stones from Moroni. Although there were periodic challenges to Smith's authority and occasional splinter groups, his status gave him the clout to weather them.
In my last post, I noted how Paul claims in Galatians that he received his revelation independently of Peter, and yet, he still acknowledges Peter as his predecessor in the faith. In both Romans and 1 Corinthians, Paul instructs the recipients of his letters to raise money for the church in Jerusalem. Under the mythicist reconstruction, the only way any of the apostles encountered Christ was through appearances, revelations, and scripture. Nevertheless, the group in Jerusalem headed by Peter seems to have some special claim to superiority that--to me at least--is not fully explained by the mere fact that Peter was the first one to receive a revelation.
I asked Dr. Richard Carrier about this in an email and he suggested that "Peter started the cult and began the evangelization abroad that created a useful network of dues paying churches and garnered support for his cult-center long before Paul joined it." While I think that this would explain Paul's deference, I don't think that Paul gives us enough information to determine how and when the practice of submitting offerings to Jerusalem developed or what role Paul himself may have played in that development.
I have a feeling that there is something that Paul isn't telling us that might better explain the basis for Peter's clout. I'm guessing that it is not as impressive as Smith's Golden Plates because Peter doesn't seem to have been able to maintain as much control as Smith did, but I suspect that it is something more than mere chronological priority.