I'm just going to leave this here--I rarely have problems with semis as a cyclist or a driver because a) most semi drivers are good and b) I think I understand the physics and try to give them wide berth. However, there are clearly some semi drivers who will insist on routing turns in intersections they really can't negotiate safely just to save a couple blocks. Unfortunately, some of them are attracted to a particular corner about 3 blocks from my home. It isn't a major problem on a bike, but in my car, I've had to illegally back up from where I was waiting for the light to change because a semi insisted on starting a right turn late on a yellow light. And no, on that particular corner, you cannot see the semi until it actually reaches the corner, so there's no warning you need to idle about a quarter block up to give the driver room.