I know what you mean. It really gets on my nerves too, especially with the added obstacles of pot holes, bumps, cracks, thick car fumes and people. I used to commute 7 miles to work and another 7 miles back, until I realized the frustration it caused was probably doing a lot of damage to my body internally. Constantly stopping and going, constantly having to hold my breath to avoid inhaling diesel fumes, constantly being on edge. By the time I got to work I felt half-dead and smelled like it too. Now I take the bus. It's just too risky to commute by bike. Biking should be reserved for recreation.