Why did McGuinness not speak out sooner?

How sweet of John Mc Guinness TD finally to speak out about the performance of Tánaiste Mary Coughlan.

But two things spring to mind. Firstly, why did it take him until now to voice his opinion of the Tánaiste? Could he not have spoken out sooner?

Did he really have to lose his job as junior minister to loosen his tongue. Secondly, he must surely be suffering from political amnesia.