Have you noticed any issues with Disconnects on that Mac? We had a user that upgraded to 10.10 and was dropping constantly. We couldn't find a reason that it would drop like that. And it only happened on 802.1x network. So it seemed to be related to 802.1x in our enviorment but it might have just been a fluke with this specific user.
In the wireless logs we'd see that the wifi would turn off randomly. We haven't enabled Airgroups though so it could be a culprit in dealing with bonjour
Wed Jun 4 11:23:37.276 <kernel> wl0: powerChange: *** BONJOUR/MDNS OFFLOADS ARE NOT RUNNING.
Wed Jun 4 11:23:38.068 <kernel> wl0: leaveModulePoweredForOffloads: Wi-Fi will turn off.
Wed Jun 4 11:23:38.069 <airportd[30]> _handleLinkEvent: WiFi is not powered. Resetting state variables.