Good idea/rubbish idea

Many years ago when I was on the late Today newspaper there was a brilliant IT guy who knew nothing about politics, economics or finance. But, boy, could he write a computer programme.
In the run-up to Budget Day, I would sit down with him and explain the intricacies of taxation. He would look bemused, ask a few questions, then go off and produce the most incredible tables that allowed any movement in tax announced by the Chancellor to be fed in and - hey presto! - seconds later these wonderfully detailed tables were produced and fed straight into the paper.
Today was years ahead of the rest of Fleet Street (in fact, no one has ever really caught up - they don't bother nowadays).
One year I asked him to do something a bit different. I wanted to work out what the effect would be of merging income tax and National Insurance so I could write a feature in advance of Budgtet Day proposing that revolutionary move. He did.
The result was so startling I never wrote the feature. It was just impossible that any Chancellor could ever be so crazy that he would introduce such a merger.
Yet in this week's Budget, George Osbornbe announced that was what he was planning to do, though not quite yet.
Haven't the Treasury got a computer expert like my former colleague on Today? Of course they have. So doesn't Osborne realise what merging tax and NI does?
Put very simply, the merger doesn't make much difference to anyone earning under the cut-off point for National Insurance contributions (about £44,000 I make it) but as soon as you go above that, you are paying an extra 10 per cent tax - except anyone earning in excess of £150,000 a year, who is already paying that amount more, until Osborne abandons the 50p rate.
So the Middle England Tory voters who aren't in the super-rich class would be seriously hit. At £50,000 a year, an extra £600, at £60,000, another £1,600, at £80,000, you will pay an additional £3,600. These are the backbone of Tory voters. Why would even this insane anti-middle class government do that?
It might make sense to merge income tax and NI, as I worked out 25 years ago, but it just is too politically difficult.