Off the screen and script, a convention - especially a Democratic convention - embraces scores of memorable events, official and unofficial. The most striking parts of the Democratic convention in Atlanta last time - bands and dancing in the streets and fireworks after Michael Dukakis's nomination - were not seen on the networks, which were showing lines of people in suits (and others in funny hats).
The most promising unoffical event this year has been hatched by a group of anarchists, who plan to march on Madison Square Garden carrying a giant marijuana joint (a replica presumably) to draw attention to Bill Clinton's stuttering admission of having smoked grass as a student.
Fewer Americans will see less of the proceedings this year than at any time in the television age. The three main networks have abandoned their traditional blanket coverage and will show only highlights and principal events, such as Mr Clinton's acceptance speech on Thursday night and Mario Cuomo's nomination of Mr Clinton the previous day.
It is an encouraging irony that, as the parties have turned the conventions into giant prime-time spectaculars, viewers have switched off in droves. The rise of the primary system since 1972 has robbed conventions of any real decision-making function. You have to go back to Adlai Stevenson in Chicago 1952 to find a convention which genuinely picked a candidate. The parties' desire to present a joyous, united and entertaining front has progressively bored the nation, which understandably prefers controversy and backbiting to balloon drops.
The traditional gavel to gavel coverage has been preserved until now by (a) the networks' residual sense of public duty, (b) the desire of the vain and powerful news anchors to have a whole week of prime time to themselves. In the straitened television economy of the 1990s, with competition from cable, local stations and video, both good works and vanity have been shoved aside.
Some Democrats regard the more compact coverage as no bad thing. In a year in which the American people have decided they distrust all politics and politicians, little is to be gained by substituting LA Law or Roseanne with a droning speech by the Governor of Georgia or a floor vote on a manifesto paragraph calling for statehood for Washington DC.
The Democrats are determined this year to appear as normal as possible. (There had been a plan to start the convention with the 5,000 delegates holding ringing alarm clocks - a wake-up call for America - but this was rejected as too goofy). If they are shown or interviewed on television - especially on local stations - delegates are under strict instructions to appear ordinary but interesting, not too clever and not too well-off.
This may be difficult. Convention delegates are different from ordinary Americans: they are interested in politics. In the case of the Democratic convention, this means they are likely to be be richer, better educated and more liberal than the average voter.
Although the Democrats have gone to extraordinary lengths since 1972 to ensure racial and gender balance at conventions - not so the Republicans - the typical delegate remains unrepresentative of even the core Democratic electorate.
According to a survey in the Washington Post yesterday, a typical Democratic conventioneer is a self-confessed liberal with a college degree, in his or her forties or fifties, earning more than dollars 50,000 (pounds 26,000) a year. By contrast, most Democratic voters describe themselves as moderate or conservative, have no college degree and earn less than dollars 30,000 a year.