I disagree - between 2007 and 2012 the majority of SOX installations in Derby were replaced with Cosmo Iridiums - they've served up to 8 years service in some cases now - I imagine they have a buy back deal with Balfour Beatty who can reuse them elsewhere, so it isn't a waste and in the process we get upgraded lanterns and reduced energy consumption with no impact on the street scene and lighting levels.
I imagine this is why the relatively recently installed nodes weren't installed on the 45/60W lanterns, which generally still run off photocells. New LED installations seem to have the nodes installed according to Mike Barford's website's latest update (
http://www.streetlightonline.co.uk/LocalLights/Sideentry/localluma1s.htm), so imagine this will become the norm when the Iridiums are replaced with LED lanterns (probably Lumas) and further reduce energy consumption justifying the invest to save measure.
Probably quite a smart move really.