The New York Times has a different story. Its Moscow correspondent says that Putin made up his Ukraine policy on the go, with only limited input from his foreign policy officials.
The decision to invade Crimea, the officials and analysts said, was made not by the national security council but in secret among a smaller and shrinking circle of Mr. Putin’s closest and most trusted aides. The group excluded senior officials from the Ministry of Foreign Affairs or the cadre of comparatively liberal advisers who might have foreseen the economic impact and potential consequences of American and European sanctions.The Times also suggests that the operation was conceived as a covert action in order not to violate Russia's position that the UN must approve international interventions. That explains Russian denials that the forces in Crimea are Russian.
It's possible, of course, that both pictures are accurate -- that Putin improvised rather than having a master plan, but that the Russian special forces sent to Crimea carried out a textbook operation.