the cyclists i've encountered while driving over the past few years have gotten better and better at being predictable, but before that i had a lot of run-ins with cyclists who would, for no apparent reason, veer 3 or so feet to the left (in front of my car) when i was about to overtake them. one cyclist threw himself bodily into traffic on a 55mph road, right in front of me, because he just wasn't paying attention. i was terrified! another cyclist hopped his bike off a curb between cars (i assume that's where he came from) and shot out at breakneck speed, and i really almost did run him over. if i hadn't slammed on the brakes, he would've been creamed. then he gave me a nasty look like it was my fault. so anyway, with cyclists like that riding around, i think there is, in many situations, good motivation for motorists to get cyclists behind them, so they can't run the cyclists over. i have sped up a couple times to pass cyclists, either to get them behind me or to take advantage of a lack of oncoming traffic. so just because someone speeds up to pass doesn't mean they are being antagonizing or asserting their superiority or whatever. it's a lot better now, though, for some reason--maybe because so many more people ride bikes in portland that there's more positive peer pressure to quit riding like an a-hole? i don't know. anyway other cyclists seem more predictable to me these days, so i generally don't want to get past them as soon as i can. in other cities it may be different; i don't know. i know a lot of drivers are dangerous and totally suck, but i bet not all of these people are being jerks.