I have driven on blue lights many times. It is not all about speed, though it is nice to be able to drive to the limit of the conditions without worrying about an across the board speed limit which may not relate to the conditions at the time and may not actually be the safest limit on that road.
It's really all about making progress. If you read the traffic correctly and pass when safe, including filtering. Timing and choosing the correct position at traffic lights helps too, blue lights or not, if the lights up ahead have just changed, slow down and watch the traffic then move into the best position to ride off when green. If the lights are on red for some time as you approach then a little more caution may be required as the lights are more likely to go green as you filter.
Riding is a skill it is not a race, if you master the skill then you will be able to travel fast (or slow) and make good safe progress without endangering yourself or others in the prosses. Just so you know, I do like to ride fast and sometimes break the national speed limit but not often in 30 zones though I did flash a camera a few months ago. Speed is not dangerous (it's fun and exiting) but bad riding/driving is. Speed is only relevant when you hit the ground, tree or third party but it's not always the reason for the accident or should I say collision.
My views only and I respect different views. Ramble over.