On Wed, 3 Feb 2016 13:00:54 +0000, dennis@home
wrote:

On 03/02/2016 11:33, T i m wrote:


As will the Garmin ... just that I have found it has chosen the
quickest that should be the quickest, if it wasn't for the fact that
there are known 'restrictions' (like a narrow bit of road that makes
it half duplex) that slow people up, but not sufficiently to become
worthy of a congestion notice.

Tomtoms would probably have noticed if someone has parked a lorry for
five minutes and caused a 30 second delay.

How though? I know there are traffic monitoring cameras on some main
routs (typically on motorways etc) but how would anyone know a lorry
was caught up down some side street used as a rat run?

I have been notified of 30 second delays while out and about.

Yes, me too, but only when on major routes and that's not necessarily
the same thing as being informed about a delay that has only been
there for 30 seconds or five minutes, specifically if not on a
monitored route or it not impacting a monitored route?

The only way I could see that sort of thing working would be if the
GPS was able to compare your actual speed with the theoretical and
reported_by_others_recently speed for that route and upload that
discrepancy to some network and then update all the other units (like
you can with some speed camera warning devices).

I mean, if a particular bit of 30 mph road was only / ever 15 mph
because a restriction made it half duplex, it's quite possible that
information could be collated by many peoples track logs but that
wouldn't be so likely to predict a broken down lorry making it a
little bit worse?

Unless it can (and I'm not saying it can't etc) ... if it was linked
into a real live traffic network using two way data from many GPS
units (or phones)? shrug

Cheers, T i m