From a priest reader:
Except when the Archbishop (or another Bishop) is celebrating here at the parish I am not inclined to concelebrate. I prefer to attend in choir as does my associate when one or the other or a visiting preacher is the celebrant ( special feasts, school masses, etc.). What is the protocol for the reception of Holy Communion for when a priest attends in choir dress? We know what it is when a Bishop is present but unsure if the same concessions go to a priest.
I agree. Concelebration should be safe, legal and rare. Attendance in choir is better on most occasions.
In that case wear proper choir dress, which is cassock and surplice, with biretta. If you are a canon or rector, etc. that would be a little different.
For reception of Communion, I don’t think there is anything to note, other than priests should always receive Communion wearing a stole. In the older form (there is no concelebration of course) you would go to the altar and receive kneeling at the step below the footpace. In the Novus Ordo, I suppose you could do this also, or Communion could be brought to you as you kneel.
I remember in Rome some years ago at a papal Mass in the Basilica of St. Peter seeing a line of canons/clerics receiving from the Holy Father. One would receive, remove his stole, kiss it, hand it to the next man who kissed it, put it on… received… removed the stole… kissed it… handed it to the next man…