I tie up a 1/2 dozen in a session and it takes about 1hr including epoxy steps.
Flies are all tied first ready for epoxy then I get two blobs of 5min. epoxy on the go mixed about 3mins apart. From there it's just a matter of going from one fly to the next.
I've spent the better part of 4 or 5 hrs tying a single salmon fly so I guess 1/2 doz. per hour is reasonable.