THERE'S one rule of thumb in the world of concert promotion - the bigger the act, the higher the risk, the smaller the profit margin. These words of wisdom come from Anders Nelsson who has been involved in the industry for almost 30 years since, at the age of 12, he started organising Friday night dances at King George V school. And they certainly ring true for the men and women who have little more than a few grey hairs to show for all the wheeling and dealing done in their effort to bring Michael Jackson to Hongkong. The contract, which promoter Allan Zeman says was water-tight, was pulled from beneath them at the last minute. The big names are where the headaches are, but they also earn promoters a name and prestige. Securing a star ''opens a lot of doors'', according to Anders Nelsson, who brought Elton John to Hongkong this year. And the fallout? It can ruin a career, but in the case of Michael Jackson and the three promoters, Artist World, Arena Group and Yiu Wing Entertainment, they should escape unscathed. It's more likely the reputation of Jackson that will suffer yet another dent - ''They don't call him Wacko Jacko for nothing,'' Nelsson commented. One negative effect could be that the public becomes a little hesitant in diving in to snap up the best seats when a tour is announced. Promoter Michael Hosking commented that there will be some people who will never forget rescheduling their summer holidays to see Michael Jackson and that he didn't come. ''Maybe it will make the promoters a little sharper and they will now want the artists to put their signatures on contracts and not just the promoters,'' said Hosking. Nelsson also believes it could affect promoters' confidence in managers and agents, who are beginning to show they do not understand the region. Tour negotiations usually begin anywhere up to two years in advance of the actual event in Hongkong. Elton John will be coming back to the territory in about a year's time - arranging that and pencilling in dates began as soon as his March dates proved successful. But Hongkong could start turning its back on big name acts, warn promoters, if ticket prices get out hand. There is a danger managers will price themselves - and their stars - out of this region, says Nelsson, as perhaps indicated by the ticket prices for Jackson, which went as high as $1,600. ''You can't really blame them for being greedy when they keep reading about the Pacific Rim booming, but there are cases of acts being paid one-third in the US of what they're asking for to come to Hongkong,'' said Nelsson. The task now for the promoters stung by Jackson is to make sure they get their money back. While over $2 million was sent to Jackson as down payment, there's also all the cash spent on promotions, ticket printing, booking equipment and seats and hiring the necessary technical experts. Sums on all the sundries are still being done, according to Artist World managing director, Florence Chan. While she says concert promotions are a big risk business, in her 20 years of working in the industry she has never had an artist pull out because of prior engagements. The fiasco has left her and the other promoters in a state of shock, she says. She, along with promoter Andrew Bull and Allan Zeman, said Jackson would be welcome back to Hongkong with open arms and they'd be more than happy to work with him. Not so Cheung Yiu-wing of Yiu Wing Entertainment - Jackson can play in Hongkong, but he won't be having anything to do with the prima donna star, was his response.