Do you suggest opposing teams should tag corey instead of Ablett? How many teams to do you know that play with two hard taggers? He doesn't get tagged because he is not damaging as ablett, wow what a crime.There are plenty of midfielders who are better than Corey, he never gets the tag and gets a alot of cheap possesions in the backline.
Assuming this is the midfield for the best 22 in the league
Other than Ablett, there are 5 spots which could be vacated by plenty of midfielders better than Corey.
You should also watch some more Geelong matches because Corey is far from a sheepdog who gets cheapies in the backline.