A year ago running up to the election, everything they did looked clever, well oiled and pitch perfect. David Cameron's electoral Rolls-Royce purred up to the winning post, his party's reputation for wrecking the public realm left far behind. Likeable, reasonable and focus group-tuned to what the British wanted, he understood Labour's legacy was a basic instinct for fairness. He knew the no-go zones – or so it seemed.

So why has he broken all his own rules in such a short time? Where did this appetite for random acts of revolutionary chaos come from? But above all, friend or foe, no one foresaw incompetence on such a scale. The saga of the NHS car crash is incomprehensible: his party seems at a loss, as ideology trumps political common sense. Cameron's campaign – "I'll cut the deficit not the NHS" – understood what was electorally totemic and radioactive for Tories.

No cuts? Former Tory health secretary Stephen Dorrell, powerful head of the commons health committee, warns yet again that no country ever attempted a 4% health cut in one year, let alone four years running. So what possessed Cameron to risk such cuts and lie about it, let alone to encourage Lansley's simultaneous "revolution"? To advertise the NHS for sale to "any willing provider", making Monitor open it to EU competition law, confirms every worst suspicion voters already held against his party.

Facing the immovable object of the House of Lords and the Dorrell committee's broadside, this week, he pulled the handbrake and Westminster reeks of burning rubber. But this "natural break" is just for advertising, to explain it better, he says, amid rumours of a cull of special advisers and junior ministers to bring in better salesmen. His own "enemies of enterprise" attack on the civil service misfired badly, as Whitehall fails to rescue ministers from their blunders.

Cutting is difficult, but ignorance of the services being cut is causing serial unforced errors. Michael Gove, like Andrew Lansley, was thought sure-footed – but he too has tripped at every step. This week saw school budgets take a shock extra £155m cut. School building, Bookstart for toddlers and sport were all mangled, then partially restored, leaving chaos. The OECD this week called for education maintenance allowances to be restored. Free schools look perilously set for eruptions. Eric Pickles's thuggish assaults on public service turned localism sour: his "abolished" Audit Commission staggers on with no substitute plan. Elected police commissioners are causing turmoil amid heavy police cuts.

The ink wasn't dry on a strategic defence review that relied on Cameron's policy of conflict avoidance when he plunged straight into Libya: now top brass want their Harriers and Tornadoes back. Transport policy has the home counties at war over high-speed rail through their gardens and steep commuter fare rises. His "greenest government ever" squanders £2bn on slightly cutting petrol prices. The Institute for Fiscal Studies says Iain Duncan Smith's promised £140 pension even for the rich is "impossible". Vince Cable's student loan budget is bust as universities charge more than expected – causing cuts in student places, bad for social mobility.

But in a week of bad news, social mobility is what Nick Clegg offered as a talisman of good intentions. Every politician is for it – so long as they ignore what it means. First, it requires greater equality – but every forecast shows the country heading the other way. Look at IFS graphs and yes, the top 1% is hit hardest, earners above £150,000 on the (temporary) 50p rate, but after them it is the bottom 10% who suffer most, the next 10% next and so on: it's regressive. Taking the low paid out of tax sounds generous – but that £200 a year is overwhelmed by the average family's extra £450 in VAT. Add in frozen child benefit and public sector pay, then add the more devastating cuts – 10% cut in childcare support worth an average £780, lost EMA worth £30 a week or the £500 cut for new mothers. Austerity babies born from this month lose £1,783 in their first year.

The IFS, that sober judge and honest arbiter, this week made mincemeat of the government's social mobility pretensions. They show it only happens in more equal countries: the UK is one of the most unequal. They say mobility needs children of higher echelons to fall down the ladder to make room: no chance of parents allowing that when the penalties for failure are so severe in Britain (nor of Cameron suggesting it). They say it needs intensive support for the youngest children – but Sure Start is being shredded. They say increasing numbers of graduates reduces wage inequality – but university places are cut. They say careers advice needs to help pupils make the right choices – but Connexions is cut and the new careers service is mooted to be online only. Crucially, they say money matters for mobility – in hard cash – but every prediction is for growing child poverty. Cameron and Clegg must surely know their mobility talk is bogus.

But they are beginning to be rumbled, as people find what ministers proclaim diverges from what's actually happening. Nowhere is this more apparent than where it matters most – in the Treasury. This week, the National Institute of Economic and Social Research revised down its estimates: the UK only achieved a faltering 0.1% growth in the last six months, while ONS figures registered a drop in manufacturing. After the "budget for growth", Ipsos Mori's poll shows attitudes shifting: 45% say Osborne is not doing a good job, only 36% satisfied. Labour is catching up on who has the best economic polices, at 28% compared with the Tories' 31%. Balls level-pegs as best chancellor at 36% to Osborne's 35%. Few think the private sector will make up for public job losses. Few think "we're all in this together", with 71% saying the poorest are hardest hit. A majority now think such deep cuts are too high a price for paying off the deficit – 48% to 41%, while 70% say the cuts are too fast. This is a rapid turnaround.

A reputation for incompetence is lethal for governments. Rattled ministers look uneasily aware that the mantras they are required to spout in public are increasingly divorced from reality. No, 88% of GPs have not signed up to commissioning: the Royal College of General Practitioners says five or six enthusiasts sign up and the entire area of 150 practices is registered willy nilly. No, 80% of people are not better off, that's misleading, reports the IFS, as people feel their household spending power shrink. Every false step in policy after policy undermines confidence: is this government also wrong on cuts, employment, the deficit and growth?