Citric acid is a good shout, but if you can get hold of sulfamic (NOT sulfuric) acid, it is much faster at removing limescale as it is a stronger acid. It does cost a bit more though…

It certainly does:

Apparently, zinc deficiency is very common in the Middle East, and one of the side effects can be aggression.

This led to Edward de Bono suggesting Marmite as a solution to the conflict in the Middle East, as Marmite contains high concentrations of zinc…

In my eyes having someone on an escooter in front of me is no different to having a slower cyclist in front. So it wouldn’t bother me.