"In response to such an account of Mr Cameron's electoral difficulties, some of the belly-achers become positively Bennite. David Cameron lost because he was not offering proper Toryism. He should have campaigned on scrapping the 50p rate and no ring-fencing for the NHS. If that had been the Tory platform, it is just possible that Gordon Brown might still be Prime Minister."
Complete and utter nonsense. Nobody is suggesting he should have campaigned on such a platform, because everybody recognises your statement of the obvious.
However: the 50p rate is economically illiterate, and there is a strong case for saying that bringing it back to 40p (where the rich still pays substantially more than anyone else) would mean everyone else would be required to pay less tax and receive more from their public services (and the economy in general). Nobody in the government is making this case, at least publicly, because the government is scared of making a complicated argument, even one that is eminently winnable. This is of course something they could be doing now they're in the first half of a term, rather than approaching a general election as you preposterously suggest. The challenge is to make the message about such a change being of benefit to the masses more than to the rich, and then hammer that message in relentlessly.
The NHS ring-fencing was recognised as an unaffordable promise early on and given that Labour was even ruling it out themselves the promise should probably have never been made. By defining himself around that message Cameron runs the risk of coming across as a promise-breaker. But worse, in defining public services by the amount of taxpayers' money poured into them, the Tories have been dancing to Gordon Brown's tune - when before, with the "more for less" stuff, Cameron showed so much promise of doing otherwise.
Nobody, anywhere, is saying either of these examples are "quick fixes" that would get the economy booming again. Trying to fix the economy at all is like trying to rotate Blackpool Tower 45 degrees using only a hammer and a screwdriver. But holding onto failed policies like 50p tax is like trying to do all that with a ball and chain attached to your foot. Pointless and irresponsible. And it's treating the voters like they're idiots who can't be persuaded of anything.
Timing is everything in politics, and the time to make these arguments is now.