Falling off workshop III

Today I had a nearly fall off the bike incident down to me forgetting that my feet were attached firmly to the bike. Low speed, lots of wobble, one profanity and I suppose you would like an explanation - cos the video doesn't make it very clear.
To begin with it is a normal day. Approach a queue forming behind the bus, the last vehicle in the queue being the tanker you can just see at the beginning of the clip. No problems so far. I point forward for the bus driver to carry on in front of me (I may be a bit optimistic that he can actually see me but I am fairly sure I could see his mirror)

Things now start to get interesting because it transpires that the tanker has failed to position himself in the road for the right filter lane in which he is parked, causing the bus to stop rather than proceed ahead through the green light as I expected it to.

I slow down to below walking speed but that isn't enough to avoid the rear of the bus; I try to put my foot down still clipped in to the clipless pedals (yes, apparently clipless pedals are attached to your feet by clipping in to them. Don't ask me why - I am as confused as you dear readers.) so I wobble madly and during the wobble manage to unclip my feet from the pedals.

So only a little falling off, not a spectacular all over the road version.

I must be getting more relaxed about the whole recumbent/clipless pedal thing if I can make a silly mistake like this... can't wait till it is all as much second nature as riding the upwrong.