I filter when appropriate and safe. I almost always stop far enough to the left to allow cars to turn right. Some cyclists feel the need to push the crosswalk signal button, which usually involves blocking right turning cars. I almost never do this. First, at most intersection, and all of the ones on my commute, pushing this button does not speed up the timing of the lights.

Often the light will only change when a car runs over a sensor in the road, or, when the crosswalk button is pushed. In cases like this, where there is no car at the intersection to set off the sensor, I will cross over and push the button.

At left turn lanes, I will get into one if it is safe to do so and I see that it will change before I can make it straight through the intersection and catch the light changing to green to go the other way.

Again It helps if there is a car to trip then sensor, and in that case I get behind them since I know I can keep up at least through the intersection. If it is a double left turn, always get in the outside lane so you do not have to cross in front of cars to get to the bike lane. I am surprised by how many don't get this.

If there is no car to trip the sensor, you can sometimes to it with a bike by riding along the groove in the pavement where the sensor is buried. (It is just a thin wire that sends a very small current to the controller when moving steel disturbs the magnetic field. Sometimes bikes spoked wheels will do it. Again, I know which ones on my commute - most of them- will do this.)

It all comes down to knowing your route if you are a regular commuter. If you are joy riding in unfamiliar roads it is better to err on the side of standard road rules.