The trouble with big jobs is that often they are just too big for any one person. Listen to the pronouncements of international investment strategists and you will hear a great deal of general talk about world economic cycles but precious little hard advice which will really help you in deciding where to put your money. Your correspondent tried to change that once when he held down a job as a regional portfolio strategist. He decided to concentrate on what was happening in individual countries in Asia and resolved to make at least two fact-finding trips a year to each of them and write a detailed report on each at least once a year. He never succeeded. What with marketing trips around the world eating up almost three months a year plus the staccato beat of e-mails popping up on screen, the phone ringing all day long, conference calls, client visits and the list goes on and on, that resolve to understand things in greater detail was soon forced to the bottom of the priority list. So when Lehman Brothers sends in a visiting pundit billed as the global head of foreign exchange research to pronounce on our local currency arrangements your correspondent knows exactly what to expect and, sure enough, that was what he got. Mr Russell Jones thinks it is a 'logical' step for the SAR eventually to relinquish its currency peg to the US dollar and adopt one with the yuan instead because of the increasing integration with the mainland economy. Chalk that one up as another gem from a guru who does not have the time to fit thought in between talk. The first difficulty is that integration with the mainland economy does not necessarily mean integration with the yuan economy. The two are not the same. The big export-processing zone we service across the border does not deal primarily in yuan. It deals in US dollars. An industrialist friend who has manufacturing plants across the border once tried to calculate it for your correspondent and estimated that only 5 per cent of the retail prices of his goods in the US was effectively yuan denominated. The figure may be higher for others but it will still be a small percentage. What we have across the border is Santa's toy shop (he moved from the North Pole about 15 years ago in case you did not know) and he does not favour confusing himself with a hundred different currencies. He buys his materials in US dollars and he sells his goods in US dollars. He even pays his workers in US dollars sometimes and lets a labour boss sort out what that means in yuan. If we are to remain integrated to this mainspring of the Hong Kong economy then the best currency to which to link ours is the one to which we already have it linked. But there is another good reason for doing so. A currency board link works on interest-rate pressure. If a pegged currency and its host currency are freely interchangeable at a fixed rate then your choice of which to hold is heavily determined by which offers the higher interest rate. Now first of all we do not have free interchange with the yuan. The mainland's capital account is still closed and do not fool yourself that any declaration of it having been opened would really mean unhindered ability to move from one currency to the other without interference from Beijing until more decades have passed. More to the point, we would find ourselves pegged to mainland interest rates. We have trouble enough when US rates restrain ours from going where they otherwise might go, but use an exponential equation to multiply that should it be mainland interest rates that govern ours. Back to New York with you, Mr Jones. You may excel as a Fed-watcher but please do not venture outside of dollar gossip.