Hooray! Railtrack wants £52 billion for renovating the railway system. Boohoo! Some £20 billion of that will have to come from increased taxation, not investment. What does that mean in real terms? Well, I could shilly-shally like other commentators, but I won't. What it means is that it will never happen.
Cost-estimating is a funny thing. Accountants and quantity surveyors treat it as a fit subject for formulae and equations, but in the end it probably owes more to a hunch and a strong dose of pessimism. For example, perplexing as it might seem to a veteran politician like Donald Dewar, the way the cost of the new Scottish Assembly shot up from £50 million to £195 million in two years will not have surprised many architects or experienced clients.
It certainly won't have surprised anyone who witnessed Enric Miralles' performance at the aa six years ago, when he was pitching for the job of chairman. On that occasion he displayed a lordly disregard for economics, even though for the last 30 years money has been at the heart of all the problems of the school.
Was he downhearted by this? Perish the thought. But instead of a discourse on fiscal probity he waded straight into the usual architects' show and tell, illustrating and describing his own work with the beguiling Iberian comic spin for which he is now famous.
'What do I know about the AA?' he asked rhetorically, waving his arms. Then he lunged over the lectern as though to embrace the sardine-packed school community and vouchsafed: 'I see it like a cloud. I never analyse it. I think we should keep it like that. It is very important. Yes and no are always the same.'
There was more in this vein, plus a thousand slides of an Alzheimer's hospital that seemed to be made of ink blots, cutups, collages and Rorschach tests. Not that anyone should dismiss Miralles' offbeat approach because of this. He may not have got that job - was that the only reason he didn't was that he wanted too many return tickets for his family - but he has landed many others, not least the great Holyrood commission awarded by the hypnotised first minister of Scotland, Donald Dewar.
Aye, but what a poison chalice! The skeletal Dewar may have been seduced by a dazzling display of very important clouds, upturned boats, cutups and collages, but that is the stuff of the lecture hall and the studio, not practical politics. What politicians like to see is an opponent impaled on the horns of his or her own ambitions, and then to strike. And for this Miralles is now their man. As detailed design progressed Members of the Scottish Parliament saw a need for more offices and a debating chamber that required repeated redesign. Miralles obliged. Then there were complications with the site. But the real killer was the example of Wales, where the downfall of Downing Street's protege in favour of the once Livingstoned Rhodri Morgan led to a swift vote to discontinue Cardiff's equivalent structure. That left the way open for the most crushing cost estimate of all by a former president of the rias - £195 million to £230 million - and the decision by the Scottish Nationalists to vote with the Tories in favour of shelving the project.
This week, if the vote in Scotland has gone the same way as the vote in Wales, we shall have to rethink those picture books on The Architecture of Devolution. With no Scottish Parliament building, no Welsh Assembly building and the Northern Ireland Assembly closed down, Portcullis House at Westminster will be the only new parliamentary building in the United Kingdom - Not quite what the government had in mind.