In article ,
Mark Brader wrote:
Off-topic. See http://www.roadfan.com/mtrfaq.html#110.

ObOn-topic version: indicates that none of the next *four* signals is red,
intended to authorize speeds above 125 mph...

You got me there

Nick, envisaging doing 125mph down the Euston Road if you get a flashing green
--
"My objective at this stage was to work about 3 days per week"
-- Richard Parker in http://web.ukonline.co.uk/richard/cv78.html