That's a problem, because Viacom needs more nay-sayers in the board room — including someone who will tell Redstone, who's 89, that it's time to spell out a succession plan (for the company and CBS, which he also controls) and explain what would happen to his shares when he's out of the picture. That's one of many reasons why GMI gives Viacom an "F" grade for its governance. The group says that it has too many entrenched directors who sit on too many company boards, potentially leaving them with too little time to focus on Viacom. Proxy advisory firm Glass Lewis also notes that it has "significant concerns" with Viacom's executive compensation practices.