I know he was showing what to do for a U-Turn but after the turn in most cases you'd keep going, well I do anyway. A little harder riding two up I might add. Not perfect but I do it.
Actually not much different to doing a U-turn at some of the smaller roud-a-bouts in side streets, same skill.
Using clutch on gear shift depends on who's advising you. Some say "yes", some "no". As far as the transmission goes I think it's ok either way.
I've done the clutchless gear change sometimes but generally "out of habit" I use the clutch.