Thats one of the old good ones, yeah. Control the choices was the favourite trick of Henry Kissinger, for example.
Ah, good old Henry...stuck by The Man, til the bitter end.
After The Machine cast Nixon aside, Henry and Dick would wander the halls of the White House, swilling gin and begging the portraits of presidents past for guidance.
Nixon went down, of course, in the end, and Kissinger was left to bitterly curse John Dean, out in the desert.
Needless to say, I have a soft spot for the man.