Opera Mobile or InBrowser (other browsers perhaps) can pretend to be desktop versions so youtube works as it does on PC with HD option available to check in player. Flawlessly on FV-1? I doubt it.
I believe I used to do something like this with Dolphin Browser, and it still directed me to mobile Youtube website. It is interesting if the above two browsers can go to full Youtube site.
As I no longer have any Android TV box in hand now (awaiting my new Amlogic box, after trying Telechip and Rockchip ones), I can't try them.