I just restricted to centre clearances because game style doesn’t influence a sides ability to win a centre clearance. Stoppage clearances can largely influenced by game style.
I agree stoppage clearances (especially raw averages instead of differential) are more impacted from game plan that centre clearances, but some teams do setup to prioritise turning the opposition centre clearances into turnovers, so centre clearances aren't a pure measure either. Hawthorn almost conceded the centre clearance early last season, but were aggressive at trying to put pressure on the next disposal, and ended up with the second best turnover differential in the competition. Tigers were a bit better at centre clearance differential, but still in the bottom half, but again they put a lot of focus on that next disposal, and had the third best turnover differential. This worked quite well for both teams, who despite being last and third last for centre clearance differential, Hawthorn and Richmond were 5th and 2nd best for inside 50 differential, which isn't bad given how many centre clearances they were conceding compared to the opposition, Essendon had the 4th worse inside 50 differential, despite doing quite well on centre clearance differential. Wish I could see stats on inside 50 from centre clearance stats to clarify how effective different teams were at nullifying opposition centre clearance wins.
I think you calling Essendon’s midfield is confirmation bias. You have to remember contested possessions doesn’t mean hard ball gets. All intercept possession and loose gets are contested possessions. In that final Essendon could get their hands on the ball but couldn’t move it effectively from a stoppage or from their defensive 50. I’m pretty sure from memory Essendon also won hard ball gets that game.
Agreed that hard ball gets are a more direct measure of what I'm talking about, but I've had trouble finding public stats showing those numbers, and contested possession numbers was the best I could find. Do you have a source which allows you to lookup hard ball get numbers for past games that doesn't require a subscription?