Heathrow Director, what a load of codswallop. I have no idea who Roger D and the others are but stop lights are simply a brighter form of holding point lights. I cannot see how the absence of stop bars makes a pilot's life any more difficult when there plenty of airports in the US busier than Heathrow that do not have them.
Before you taxied to the holding point and waited for line up, now you taxi to a stop bar and wait for line up. The difference is that once you were informed by voice, now you have to see some lights go out before you believe the voice.
The voice and the lights button are activated by the same controller so there is still nothing between you and a controller induced runway mishap except your own situational awareness.
I stand by my statement that stop bars have created more problems than they have solved.