SO, are the “red lights flashing”, David Cameron was asked at his manifesto launch – or are we cruising to the “sunlit uplands”?

The question effectively nailed the screeching U-turn the prime minister was performing on his party’s election campaign, from sombre to chipper in one swift costume change.

Only a few months ago, the prime minister told us “red warning lights are flashing” on the economy and his campaign has pointed to a long hard slog back to prosperity.

Now, the Tories were evoking sunny memories of Jerry and Margo enjoying ‘The Good Life’ in 1970s Surbiton – as he namechecked the title of that much-loved sitcom no fewer than 11 times.

Gone were dour mentions of the ‘Long Term Economic Plan’ in favour of voter-friendly – and expensive – promises on housing, childcare, tax cuts and the rest.

There is no doubt it is the U-turn that Conservative candidates across the land have been crying out for and will be delighted to take back to the doorstep.

The iron grip exerted by Lynton Crosby, the prime minister’s chief strategist – and architect of the narrow, negative campaign – has provoked growing resentment.

After today, Tory candidates in marginal seats will be more confident they have a message that can inspire wavering voters, particularly young families, to stick with their party.

The Right to Buy extension, in particular, got a collective raspberry from the experts, but its overall impact may not worry tenants effectively being offered free money to own their homes.

But the downside of this extraordinary political cross-dressing – making the Tories suddenly the big-spending party – is that Mr Cameron loses credibility as the trusted option.

The prime minister is now promising ‘The Good Life’, but his Chancellor is planning massive spending cuts after polling day, even more severe than we have seen so far.

What about voters not living the good life, or fearing those cuts will make their lives worse? Will the Tories seem out of touch?

Most strikingly, we now know the ins-and-outs of complicated housing policy…but we still have no clue where most of £12bn of welfare cuts will strike?

As another questioner put it: “Why are you telling us about the nice stuff, but not the nasty stuff?”