There are times when the deer are simply not moving and you're forced to make something happen. Maybe you're up against a full moon or hot weather. This is when a silent drive to force deer to move should be considered.
By silent drive, you're not yelling and making a commotion to scare the deer. When deer are panicked, they're liable to bust out of the cover on a dead run, and any shot you get will be tough to make.
A silent drive is different. It means playing the wind to carry the driver's scent into a bedding area. That makes the deer concerned enough to sneak away from danger but not panicked enough to run.
When you're setting up a silent drive, it's important to know the lay of the land and how deer move from one patch of cover to the next. An aerial photo is very useful for finding bottlenecks that deer travel as escape corridors, but there's no substitute for having an intimate knowledge of the place you're hunting and for having watched deer move through there in the past. On a silent drive, I try to think like a deer and determine how the deer will react to a threat.
Safety is the primary concern on any deer drive. The hunters should wear hunter orange, even if the law doesn't require it.