The English language is confusing enough without us fly guys and gals making it worse.
The term FLY TIER is the accepted and recommended usage according to the Outdoor Writers Assocation of America (OWAA). Wading around fly tying literature is an outright mud puddle of twisted usage. Tyer, tye, tie, tier are used interchangeably, and the game seems to be who says it which way.
Making things wobby beyond repair, is the magazine Fly Tyer. In a recent email exchange with Canadian author Paul Marriner, he mentioned he had a conversation with the folks at Fly Tyer, and their comment was, the name of the magazine was chosen for GRAPHIC reasons, the nice repetition of the lower case Y. If you look inside the magazine itself, they use the correct terms fly tier and tie.
So as much as humanely possible, we are adhering to the usage recommended by OWAA. This is as much for our sanity, as anything. Let me know when we slip up, thanks.