Actually, I was a bit late for the trip, and when approaching the Opera someone yells “here comes the circus clown!” 
It turned out that was @ruari who somehow managed to get behind me, even though he arrived before me.
Also, I knew he wouldn’t come, because he had said he was otherwise occupied. Turned out he had a sudden opening, and was also the only one showing up for the trip, which turned out to be great, and quite long with only the pair of us.
Also, I made the mistake of staying on the road instead of following @ruari on the sidewalk when we approched a barrier that only lets the bus through. So instead of hopping up on the sidewalk and risking a UPD, I went for the safe choice which was to climb over the barrier while rolling my 29er under it, and remounting on the other side. No feet on the ground, even if that counted as a dismount I guess. A planned one at least? 
That was a truly graceful manoeuver, as Ruarí commented. 