From one of the Google Nexus 4 product forums regarding the bad wifi/bluetooth interaction on the Neuxs 4:
The Google rep I talked to said this was intended functionality of the device and there is nothing to be done:
Of *course* this is "built in functionality. Of *course* Google designed the phone so that you could not use wifi and bluetooth at the same time.
Oh, and by the way, telling little white lies is a little bit evil.