Vale was named to a role that made him heir apparent CEO just three weeks ago. Not that people loved the guy but he was one of the few "tell it like it is" people around.
So, really, Mike and Monish and Board (yes, talking to you too) do you expect us to believe that Vale had some scandalous liason with someone in the organization? Where is the frigging transparency? At least when Boeing had a CEO who couldn't keep his zipper up (and messed aroung with a direct report) the Board was transparent about it. Then thankfully they took Mcnerney away from 3M.
When things like thus happen, one of two things can come of it. Either you let the rumor mill flow and distract 90000 employees or you come forward and spill the beans. Sorry, but you have zero trust anymore Mikey!