Still another issue is Caltrans' requirement that no more than 50% of the contractors' activities be on the critical path, where there is no float. But schedules can't be built like that, says the construction manager, especially for road jobs where most of the work is sequential.

Such issues may be why some construction managers continue to see float in terms of legal exposure, not as the objective creation of honestly made arithmetic calculation.

"In my opinion, schedule float belongs to whomever [owner or contractor] owns the schedule risk," says Daniel P. McQuade, president of Tishman Construction Corp. of the West, Midwest and New England.

"The benefit and ability to manage float should always follow the responsibility of managing and meeting the schedule," says McQuade. He says float is one of the most important and least understood aspects of project management.

But where does that leave the notion that float belongs to the project? That's an idea that still seems idealistic and far away.