I was doing some thinking the other day, we all know filtering not only saves us and everybody else time, but also lowers your chances of getting rear ended. However, when we take off from the lights at the head of the pack do we expose ourselves to increased SMIDSY risk. Consider riding on a typical 6 lane suburban arterial road road with parked cars and side streets all over the place. If you filter and take off from the lights ahead of the pack, and build up a nice buffer between you and them, you effectively become the only thing on the road and a very small one at that. In my personal experience, situations such as these often are perfect conditions for a smidsy incident, often from a side street or drive way with parked cars obscuring vision. Clearly there is a trade off, i think its an interesting question. Which is the better option.