Mark Carney is proving to be a lucky general who has won the important battles Napoleon said he would rather have lucky generals than good ones. So far, Mr Carney has been of the lucky variety. By the time he arrived, growth had already returned, making the "forward guidance" he provided to underpin confidence in the economy look redundant before it could be announced. One member of the Monetary Policy Committee, Martin Weale, recently expressed doubts on whether it has had any effect at all. Yet growth is growth and, whatever its causes, it scarcely seems to matter. Besides, any scepticism there might be about "forward guidance" as a way of generating growth can be answered by pointing to other possible benefits. Thanks to forward guidance, it is now possible to be clearer about what monetary policy is trying to achieve. The growth objective has become more overt and the inflation target somewhat diluted. Overlaying the inflation target with a specific employment objective has made it possible to be more certain about when the present, abnormal monetary conditions might come to an end. Last summer's "taper tantrum," when markets reacted with dismay to Ben Bernanke's warning that quantitative easing would be coming to an end, demonstrated just how difficult it is for central banks to wean their economies off unconventional monetary support. Thanks to forward guidance, in Britain we have good warning on precisely what would trigger higher interest rates. There is plenty of debate about when the new employment target might be reached but at least we now know what the Bank of England is aiming at. Before forward guidance, the position had become hopelessly confused. The Bank of England seemed to be winging it; the inflation target had plainly been put on the back burner but it wasn't entirely clear what had replaced it. Nor is it just on growth that Mr Carney has been lucky. For nearly five years, we've lived with Bank of England forecasts that consistently over-predicted growth and under-predicted inflation. Since Mr Carney arrived, the position has reversed. Inflation is going down just as growth is picking up. The Bank of England's forecasting record continues to invite ridicule but to under-predict growth and over-predict inflation, which is what seems to be happening now, is obviously a much more comfortable position to be in than what went before. The economy seems finally to be behaving itself again, with the return of non-inflationary growth. In other regards too, Mr Carney has ticked all the boxes. One of the reasons he was brought in was to rebuild bridges with the City, after the stand-offish and sometimes overtly hostile approach of his predecessor. Not content merely to re-open channels of communication with the City, the new Governor has gone out on a limb to champion its interests. Both domestically and internationally, Mr Carney has become something of a cheerleader for finance, which he sees as an outstanding growth opportunity for Britain. Again, this is a marked change of approach. The previous incumbent seemed determined to cut the City down to size after the disaster of the financial crisis. This has been replaced with a mindset that promotes finance and credit expansion, subject to adequate supervision. Finance need not be dangerous, Mr Carney believes, provided it is well regulated. In Europe too, Mr Carney has actively engaged, leading to a more accommodative view in Brussels and beyond of capital market activity. Internationally, Carney has already helped to put Britain back on the map in his position as chairman of the Financial Stability Board, the organisation responsible for the global reform agenda. Mr Carney's other big job was to modernise the Bank to make it fit for its additional responsibilities in banking supervision, financial stability and so-called "macro-prudential regulation." This is the boring, less visible part of the task but, on any long-term view, perhaps just as important. It is also in some respects the most difficult part of the job. Regulation is judged not so much by its quiet successes, which tend to be taken for granted, but by its high-profile failures. It's hard to measure progress against such a yardstick but insiders already speak of a wind of change sweeping the Bank of England's stuffy old corridors. There's a new sense of mission, and optimism, about the place. None of this is to denigrate Mr Carney's predecessor, Mervyn King, who did much of the ground work for the present revolution and put his reputation, and the Bank of England's, at some risk in fighting the downturn with bold and decisive action. By the end, he despaired of its effectiveness but, in truth, the economy was already turning by the time he left, leaving Mr Carney to take the credit. In any case, so far, so good. There will be a time for criticism, no doubt. Whether Mr Carney can calm the already plainly overheating housing market without having to raise interest rates remains to be seen. His favoured method - use of credit controls - is all very well but has a nasty habit of creating its own problems. Nobody would welcome the return of mortgage queues. By using forward guidance to hold interest rates down, the Bank of England may also leave itself with more to do later, risking a hard landing when inflation returns. What is more, if, at the end of his five-year term, Mr Carney has only succeeded in generating another, unsustainable consumer boom, then no one's going to thank him for it. The supply side measures necessary to bring about a more balanced economy are not in Mr Carney's gift. These are matters for politicians, not central bankers. All the same, within the confines of what can realistically be expected, Mr Carney gets an A star for the first six months.