Despite the article I think this potentially puts to bed the tanking/DB relationship issue (it may still have been a factor) but at this time he was still clearly in love with the club and leans more the the fact that at the end of the year he was offered a lower contract and potentially less opportunities beyond this year.
There are many reasons for this including his injuries, lack of pace, good years by Moloney and Jones and Valenti coming though as a handy back up, plus the potential of 2 eliete mids with picks 1 and 2 and the need to put games into them to fast track their development. Not to mention Grimes, Blease, Strauss etc.
Clearly his value to the team would be lower now then when he signed the last one.
On the flip side, Carlton are about to lose Stevens (and free up some cash) and McLean is a very hand replacement.
You will notice in the article on the MCF site McLean says "I have come to the decision that the best thing for my football career is to move on from Melbourne. While it has been an extremely tough decision as I have given the Club my all, I am confident it is the right one for both parties"
Best thing for his career (more opportunities/money), right one for both parties (we move on a surplus inside mid and gain a first round draft pick). It really sounds like a win/win to me.
McLean is a big loss due to his passion and leadership but I think this is the right move by the club if we are serious about winning flags!