Director term limits: a tool to mitigate entrenchment or mis-guided thinking?

The FT ran an article on July 13th 2015 entitled "MSCI: board term limits are misguided".  Sophia Greene writes that the data provider has completed analysis showing that a move towards director term limits would not necessarily result in improved performance. In fact, they suggest entrenched boards may be associated with positive firm performance. The article cites Tootsie Roll, the US candy maker, as an example of an entrenched board and firm outperformance.   

This position contrasts with what goes on here in the UK, and reminds me of the Higgs approach to director tenure which suggests a term limit to bolster independence.  But was is independence and do term limits guarantee it? Last year, the Harvard Law School Forum on Corporate Governance explained that shareholder activist groups and advisory firms like ISS value term limits for directors, see http://corpgov.law.harvard.edu/2014/05/22/renewed-focus-on-corporate-director-tenure/.  Does term limits mitigate entrenchment or is it mis-guided thinking?