Edinburgh tram extension on track for next spring? Now that's what I call 'optimism bias' – John McLellan

As Sunderland comic legend Bobby Thompson used to say, “why I’m not an engineer”, but even for the untrained eye there is a staggering amount of work to be done if the three-mile line is to be operational by spring next year, as promised.

At a stretch that’s 11 months away, and but while today’s report says 82 per cent of the track is laid – nearly a fifth still to go – what it doesn’t mention is that, after three years’ work, five of the eight stations have not been completed and nearly three quarters of the pylons have still to be installed.

The drone video gives a bird’s eye view of the zany bike lanes on Leith Walk, but also shows that most of the major junctions are incomplete and some utilities work is still going on after all this time.

The original minimum cost estimate of £207m included a six per cent “optimism bias” but only the project team will know if that’s really on schedule, but with construction inflation now running at 11 per cent who knows what the eventual bill will be.

And with 2019’s passenger projections now wildly out of date, councillors should be asking for a new appraisal of the financial position. And forget trams to the Royal Infirmary.