On 2017-02-15 15:02:33 +0000, Roland Perry said:

There will usually (always?) be two red lights. And in any event, green
doesn't mean "full steam ahead", rather than "proceed with caution".

Yes, with road traffic there is, unlike railway signalling, nothing
ever that says it is absolutely safe to proceed. However, I suspect
most drivers don't treat it that way.

LEDs of course reduce the chance of this, and these days it should be
reasonably easily possible to make all the red lights provable and in
the absence of them all working turn them all off.

Neil
--
Neil Williams
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