It's very easy to believe that Cheney did (does):
All the best details from Barton Gellman's new book on Vice President Dick Cheney. - By Juliet Lapidos - Slate MagazineSure. I believe it.
.... Page 158: Addington didn't like the idea that the speaker of the House and the president pro tempore of the Senate are included in the order of succession. An unnamed Cheney admirer told Gellman that the vice president and his staff had 'plans' for an alternate succession, 'and their plans were going to be by fiat.'