You know there's an election coming when politicians start dangling the prospect of super-duper new infrastructure projects in front of voters.
The fact that, even if they eventually get the go-ahead, none of these projects will see the light of day for a decade or more matters not a bit.
The Government is now considering not one, but up to six transport projects to cater for the needs of the growing population of north Dublin. A public consultation process was announced yesterday.
You just knew that we were losing the run of ourselves when Bertie Ahern's government unveiled plans for Metro North, an underground railway running from St Stephen's Green to Dublin Airport, and Metro West, another railway which was to run from Swords to Tallaght, in 2005.
Even at the time, with Celtic Tiger hubris approaching its zenith, these projects and their enormous cost, an estimated €2.5bn for Metro North alone, seemed to border on megalomania.
Then came the post-2007 bust and it seemed as if both Metro North and Metro West has disappeared into some bureaucratic black hole never to be seen again.
Unfortunately, now that the economy is recovering, some of the white elephant projects of the Celtic Tiger era seem to be re-emerging.
We are now being told that a pared back version of Metro North would cost "only" €2.86bn and be completed some time in the 2030s.
Somebody needs to shout "stop" before this nonsense goes any further.
Metro North was a turkey when it was first proposed almost a decade ago and, guess what, it's still a turkey.
If Metro North is resurrected it will mean that many other public transport projects that could be completed much more quickly and cheaply will be shelved.
One of these is a spur from the DART line at Clongriffin to Dublin Airport and Swords.
This would at a stroke quickly eliminate one of the gaping holes in the capital's public transport infrastructure, the lack of a direct railway link between the airport and the city centre.
The cost of such a spur has been estimated at €790m, a little over a quarter that of Metro North.
Another project on Mr Donohoe's list is the installation of three new rapid bus lines at an estimated cost of €330m. Between them, the DART spur and the new rapid bus lines deliver lots of bang per buck quickly.
They can be brought on stream for a combined cost of less than half that of Metro North and more than a decade sooner.
So why is Metro North still even on the agenda? Why has it been apparently rescued from the black hole?
It is hardly any secret in political and administrative circles that senior figures in the county of Fingal, formerly north Co Dublin, have their hearts set on the Metro North.
This prestige project was to have its terminus close to the Fingal County Council's swanky new offices in Swords. By comparison a mere DART spur doesn't cut it.
While municipal pride should be encouraged it's a very different story when public transport investment is being delayed in favour of over-the-top projects that will cost much more and take far longer to complete.