Was there a Venezuelan plot to overthrow Raul Castro?

Former Mexican foreign minister and noted Latin American politics scholar Jorge Castañeda has a piece in this week's Newsweek, positing the fairly explosive theory that the two senior Cuban officials fired by Raul Castro this month were plotting a coup against the Cuban leader with the assistance of Venezuela's Hugo Chavez. It's a fascinating piece complete with palace intrigue, betrayal and coded messages hidden in baseball metaphors. But is any of it true? 

CNN.com has a lengthy piece today featuring the baffled reactions of Cuba-watchers to Castañeda's theory:

Robert Pastor, who served as a Latin America National Security adviser for President Jimmy Carter in the late 1970s, returned Saturday from a weeklong visit to Cuba. Pastor said he wrote Castaneda a letter upon his return expressing his disbelief in Castaneda's contentions.

"This is Jorge at his most creative," Pastor said Tuesday.

Louis A. Perez Jr., a Cuba scholar who has written 12 books on the nation, also expressed his doubts.

"Where is this coming from?" Perez asked. "I operate with the idea that there has to be some standard of plausibility. Is there discontent in Cuba and was Lage seen as the heir apparent? Yeah, that's the conventional wisdom since last year. But that there's a conspiracy between Lage and Perez Roque? I don't think so. It would be helpful if the people who write these reports cross the barrier of speculation."

Castaneda freely offers that he has no proof, calling his thesis "informed speculation."

"I have no way to substantiate any of this," he said by telephone Tuesday from Mexico City. "I have no evidence of it."

To be fair to Castañeda, "informed speculation" is probably the best we're going to get in terms of Cuban political analysis at the moment. His theory seems as good as any of the others (It is a bit strange that Chavez hasn't publicly commented on any of this yet.) and at least it has the virtue of being entertaining.