Out of interest what sort of car do you drive?
It sounds to me that you are worried about the position at Stationary or near stationary traffic.
Often a biker may well make a move to filter but the particular wing mirror height of the car being passed prevents a straight forward manouver. In these situations it is normal to "sit there" and when the traffic to the right moves gain enough room to pass and proced with filtering the traffic.
As it is I actually can identify with the two rider types but here's a couple of others for you
The Advanced Motorcyclist - you never really notice him/her they move with stealth and progression that does not rely on you ever realising they are on the road
The London Courier - He will just remove the obstructing wing mirror thereby removing the problem for every one else
This is not meant to be a challenge or anything but have you ever ridden a motor cycle? Actually getting on one really opens your mind to the vulnerability but also the tremendous observation advantage a biker has. The reality is that a good biker knows more about what is happening on the road ahead, behind and to the sides than a good driver.
Riding a bike well is an activity that engages all 5 senses:
Sight - pretty obvious (used by both drivers and riders)
Sound - with modern car design a driver no longer hears most of what is going to help him
Touch - Feedback from the bikes suspension, and engine revs are a key bit of riding, using these alone I can know pretty accurately what speed I am doing without ever looking at the guages, in fact I never/rarely do hence I tend to run out of petrol
Speech - in town yelling at pedestrians is a great defence
Smell - this is the biggest difference, I can smell hazards - diesel, hay, clutch burn, oil burn, smoke all these are examples of stuff that their smell has actually given me early warning of hazards
Above all riding position and the ability to use the width of the carriageway to gain an observation advantage is totally misunderstood by non riders, my mum (64) was giving me ear ache over the way bikers "weave around" when they are following cars so I took her out on the bike with an intercom fitted and gave her a commentary ride, explaining how road position was adding to view as we rode, she could see over my shoulder. Now she understands
Actually here is an offer, I will gladly take any non rider on this site pillion so that they can understand the bikers point of view. I am in the south of England, we have helmets ranging from child size to medium adult available.