He failed to deliver when marginalised by the mercenaries Remy and Ba. Other than that he's generally always scored goals. He got us 5th in 2012, kept us in the PL in 2013 and has basically repeated that in 2015.
Bit weird that having Spurs in 3rd place form for his entire time there is somehow negated by an attacking style of football and means of getting appointed, mind. Sounds like biased drivel to me.
He's captain because he's an extension of the 'yes sir, whatever you say sir' attitude prevalent at board, management and coaching level. Nolan wasn't, and was sold.