Police spotting (junction watch)

What I mean is - it's natural instinct to go to the front of the queue if you can. You might feel safer and you will make more progress. One of the nice things about cycling is that you can do this.

If you see a green painted box with a bicycle in it, that looks like official encouragement. And yes - everyone else does it.

But it's not always safe to go to the front. When filtering you might be stuck by oncoming traffic, or someone else filtering. Or you might end up at the front with nowhere to stop safely.

Agreed, but like it was mentioned before, cyclists will filter to the front regardless of there being a green box or no green box. Most people do it because everyone else is doing it and they don't think for themselves.

And if a cyclist is stupid enough to filter down the left of a left indicating lorry when the light could turn amber/green imminently. Well, that's their problem and its no ones fault but their own for not thinking.