The Japanese security checks were like those in Zurich, rather than like those in Birmingham. That is, they did not ask people to take their shoes off, but if the metal detector bleeped, people would have to go back without their shoes. However, the difference was that the Japanese security people provided slippers for those who had to take their shoes off. I guess the Japanese are used to handling shoes-off situations.
Personally, I think the Birmingham strategy of making everyone remove their shoes was more sensible. It prevented delays and made sure that everybody's shoes were x-rayed. Think about it; if you were a terrorist, would you hide explosives in boots with metal buckles and zips like mine, or in soft sneakers with no metal?