I have seen the same things you guys have seen with Post, however I am prepared to give him a break on the grounds that he has no decent help on the last line. Cale Hooker has the luxury of having Fletcher on one side of him and McVeigh on the other, that's 500+ games, poor old Posty had Grimes helping him down back who has a whopping 9 games under his belt, sweeping around the behind them was a first gamer.
I think Post can continue to benefit with ongoing quality coaching and a bit of experience around him on the field.