"The potential sudden removal of Apotheker as CEO -- and the fact that such Board discussions were once again leaked to the press -- are likely to further undermine the Board's already fragile credibility," his report states. "Our conversations with major shareholders also indicate that they have been disgruntled with the Board, given it has made and approved a series of decisions (Hurd's firing; Leo's hiring; approval of the Autonomy acquisition; the premature announcement of the exit of the PC business) that many shareholders believe were poor decisions and misaligned with their interests."

HP also should have conducted a proper executive search, Sacconaghi argued.

"We would view any decision not to conduct a comprehensive search of internal and external candidates for a permanent CEO role as unsatisfactory and unnecessarily hasty," the note states. "We also believe that shareholder reaction to Whitman as a permanent CEO would be mixed."

HP decided against conducting an outside search for a new CEO for a number of reasons, according to Lane. "We knew we had outside options, but we had fairly recent data from a search conducted last year. There are good people out there."

"We looked at inside candidates who are not ready," and Lane himself "looked at an interim role," he added. But from the beginning, Lane expected Whitman to emerge as the top candidate, and the only question was whether she'd commit, he said. "If we thought there was a better choice on the outside, we would have conducted the search."