Perryman - I see ambulances coming out of the end of St David Road on regular basis. If the road was re-opened at the top to rat-runners, I can imagine the ambulances getting stuck in a line of traffic trying to turn out on to the South Circular. I remember when it was open as a rat-run and there were regular tailbacks right back to the turning for Sainsbury's car park. If an ambulance put its sirens on, the only thing cars in front could do would be to force their way out onto the South Circular, hoping traffic coming around the corner would stop for them. Not an ideal situation. With only a few cars at the junction with the South Circular, ambulances can easily get around them on the right hand side where the junction widens significantly.