Memorable Olympic moments often fade. But events have conspired to keep one alive from the Beijing opening ceremony. That was when a little girl lip-synched the anthem Ode to the Motherland while it was sung, unseen, by another girl deemed by state leaders not pretty enough to go on stage. The explanation that the decision was made in the national interest was rightly condemned, because it sent the wrong message to young people - that today's China puts looks ahead of ability.
It might have been largely forgotten but for two reminders. The first came on another defining occasion of the early 21st century - the January inauguration of America's first black president - when it emerged that a 'live' performance by a string quartet was pre-recorded to ensure sound quality in unusually cold conditions. The Americans made a similar national-interest argument that the occasion had to be perfect.
The two incidents are, of course, not comparable. But at least the mainland officials who made the switch found themselves in good company.
Now the culture ministry has called the incident to mind again by introducing from next month a ban on lip-synching at public concerts, backed by heavy fines.
The reason in this case is the public interest. The practice of lip-synching by artists, usually to records of their own work, is rampant on the mainland. It cuts costs for concert organisers, but the authorities regard it as cheating the public. The new law was approved in July last year, before the Olympics. Ironically, the lip-synching at the opening ceremony was, in spirit at least, out of step with the law.
The ministry's intentions are good. More opportunities to perform live would help the development of young concert artists. But lip-synching is so much a part of the entertainment scene that it may be difficult to pay more than lip service to enforcement of and compliance with the new law.