2172607 said:
There is one fundamental difference. There is no need for motorcyclists to be given a breathing space at the front, they can sit in a stream of traffic perfectly well, it is just a desire to get away first and fastest in their case.
It is not
just that. That may be part of it, but it is not just that. Generalisations about motive and mindset may not always be helpful.
As a motorcyclist and cyclist in London for many years, I liked to start at the front of a queue on both kinds of bike.
Sometimes (particularly when working as a courier) it
was to allow me to get away firstest and fastest.
Sometimes it was because there is a sense of vulnerability in the midst of a stream of four-wheeled vehicles that one simply does not experience at the head of a line. This is much as it is for bicycles.
Sometimes it was because a passenger made the whole plot slightly less stable and responsive, so a little extra room was a blessing.
I haven't ridden a motorcycle since the early 90s and have no experience of ASLs when riding one, but I find it quite understandable that a rider would squeak his or her way to the front to benefit from one. I think I probably would, if still riding.
As to the 'fastest' element of your assessment of the desire of a motorcyclist in traffic, it is terribly difficult on almost any motorcycle not to the the fastest away. It's not some sort of Valentinik-wannabe race instinct kicking in.... It's just the way mtorcycles tend to be powered and geared, all the way from a Benly to a Buell.