I can't speak for an East African safari, but with the very private safaris of the Okavango and Zambezi, one learns very quickly that stealth is the key to keeping the animals from scampering away and to continue doing their natural animal-thing. When you've got a lioness and her three cubs feeding on a recently killed warthog, and all of this is happening less than 10 feet from your camera lens, it's really not the time to to speak up and say, hey, honey, hand me the video and the tripod.
I somewhat jokingly (somewhat) say to Rusty (as in: all the time) that we really (I mean really) need to work on our communication skills. Rusty would tell you that all we need to improve our communication is a quieter wife. Still . . . when called upon to do so, our communication is actually superb . . . as in, eye movements speak volumes (so does a kick underneath a table), and body language says it all. Such was the case the other day when the monkeys came to lunch, less than ten feet from our poolside railing. We were able to trade positions and cameras with the stealth of an F-177. For the howler troupes that live near Mil Colinas, this is as close as they've ever come.