Tony Blair's unexpectedly sweeping reshuffle raises as many questions for construction as it answers (pages 22-23). Few will bemoan Stephen Byers' departure, and Alistair Darling has said that he's not going to "tear up" the 10-year transport plan. But then he was drawn into an ugly spat with Downing Street after he rejected Lord Birt's toll motorways. So who exactly is driving transport policy? Similarly, Lord Rooker's arrival as housing minister will bring hope that the botch job that is social housing policy – failed stock transfers, aborted PFI pilots, thousands of condemned homes – can be repaired. But what of Lord Falconer's planning reforms? Roger Humber sees Rooker's arrival as "a wonderful opportunity" to rethink his green paper (page 31); but a "gritty, pragmatic and shrewd Brummie" may prefer not to enter the planning maze at all.

Aside from a few new faces, the most striking feature of the reshuffle was yet another carve-up of the Whitehall machinery. A year after the biggest overhaul for nearly 40 years, Byers' DTLR has been broken up to make way for the creation of a transport ministry and the preposterously entitled Office of the Deputy Prime Minister. At a time when the government is seeking to deliver epochal reforms of public services, many civil servants will be distracted by questions of pay, pensions and who has the best view from their office. In the private sector, what contractor could hope to flourish after two mergers in a year?

Even more unsettling is the realisation that it not strategy but events, and the headlines they generate, that are behind these changes. It only takes one crisis for Blair to take the wrecking ball to a department of state. Thus foot and mouth led to the culling of the Ministry of Agriculture, and Byers' demise means the end of the road for the DTLR. That's politics, of course, but it creates weird anomalies for construction: safety is now at transport, presumably because of Potters Bar, and the biggest shake-up in Building Regulations for a generation falls to an as-yet-unnamed minister in Prescott's new empire. But it would be churlish for construction to protest too loudly about all this. After all, it was the industry (manufacturers in particular) that lobbied for the move to the DTI a year ago, and it's still there. Construction minister Brian Wilson wasn't moved either; indeed, his brief was only recently altered so he could devote more time to the industry. And one department that surely must be safe from the Blair bulldozer is Trade and Industry.

For all the disruption, isn't the new structure pretty sound? Arguably, transport should have its own department now that it's third behind health and education on the political agenda. And as for construction, isn't it fair to separate sponsorship and regulation, as environmentalist George Monbiot suggests? Possibly, but there may be an even stronger case for the opposite – a single ministry embracing planning, housebuilding, construction, safety, regs and design. To call it the Ministry for Construction would sound too much like special pleading – particularly in Building. But how about the Ministry for Regeneration? Yes, another ruddy acronym. Yes, more upheaval. But it would make for more coherent policies, and clearer lines of responsibility: in other words, "joined-up government". Now, whatever happened to that great Blairite crusade?