Police spotting (junction watch)

Sometimes you can't. Or it's more dangerous to stop than not.

The rule is the same for red lights in a car - one of the acceptable reasons to go through is that you were going too fast to safely stop when the lights changed. That's why people speed up to "catch" the lights

So make that the rule, if you can't stop safely before the first line then go through. It's unnecessarily complicated isn't it?