Don’t raise Todd Juenger’s name if you happen to run in to Viacom CEO Philippe Dauman this morning. The Bernstein Research analyst — who’s also Wall Street’s most vigorous Viacom critic — just unloaded both barrels at the spreading view that the company is poised for a rebound. Shares are +9.6% since New Year’s Day, closing at $57.82 yesterday: As I noted this week, several investors and analysts say that ratings either have or should improve at Nickelodeon and MTV, and will start to look really good when compared to early 2012 when Nick hit the skids. Don’t tell that to Juenger, who just reiterated his “underperform” rating and $52 price target. “We attribute Viacom’s poor ratings primarily to a lack of institutional creative capability, perennial under-investment, excessive reliance on too few hit programs, and liberal online distribution” to companies such as Netflix — which cannibalizes TV viewing — he says. As a result, he places a “low probability on the likelihood of a ratings turnaround.”

That’s worrisome, he adds, because Viacom shares are no longer a bargain. Although they look cheap compared to expected earnings, a different picture emerges if you compare stock prices to the company’s cash flow (or EBITDA: earnings before income taxes, depreciation and amortization) — which he considers to be a more revealing barometer. Viacom trades at 8.8 times expected cash flow making it more expensive than Time Warner (8.6x), Disney (8.6x), CBS (8.0x), and News Corp (7.6x). “Why would you pay a premium for a company with consensus EBITDA growth of only 4%, on the chance that Viacom ratings might actually someday stop declining, when premium franchises like [Disney] or [News Corp] can be bought for less?” he asks. He’s also cool to Viacom’s efforts to impress the Street by returning cash to investors — including with a planned $2.5B stock repurchase in the current fiscal year. That doesn’t enhance Viacom’s value, Juenger says adding that “we’d rather see them invest behind their brands.”