I think people take a very idealistic view of what goes on within the club. To suggest that they are tanking at this point of the season just doesnt make sense. They are simply not good enough to be winning games.
Firstly, Dean Bailey does not have the luxury of tanking. If he wants a career as an AFL coach he needs to win games, and so is busting his gut to do so.
Secondly, with the exception of a couple of jusy a few senior guys, the players are desperately trying to build and consoliate careers. Most guys just want to play well so that they ensure they are in the team ahead of guys competing for the same spots. Most can not afford to play deliberately below their best, and still have AFL careers in 2 years time.
Teams might tank in the last round if they are in a position, but not for half a season or more - it just doesnt add up.