“Actually Jesus breathed the Holy Spirit on the Apostles shortly after the Resurrection. The two stories don’t mash.”
That’s not necessarily true. This giving of the Spirit as reported by John was not followed by the evidences of the Spirit as after Pentecost nor were all of the apostles there to “receive” the Spirit as commanded by Jesus. In fact, it is much like the initiation of the last supper; no effect. Life went on as usual; they hid in their room from the Jews and went back to fishing. After Jesus ascended and sent the promised Holy Spirit he came in power on the assembled disciples, all 120 of them, and without the command to receive him, and transformed the disciple group and gave physical evidence of his presence in their lives. Much the same as when different groups believed and the Holy Spirit was given by the laying on of hands by the apostles.
It looks to me like the John event was a specific granting for a specific purpose rather than the promised sending when Jesus ascended to the Father.
You may be right. There seems to be a discernible difference in kind between that event and the Penetecost.