Yes, there is definitely a shift since 2013 in total tackles, when the top four sides on the ladder also had the most tackles.I don't think it has. We have gradually transitioned from a high tackling team to a low tackling team. The game is evolving and I think Ross is moving with the trend.
2013 we were 6th in the league for tackles
2104 we were 10th
This year we are 12th
This season, Hawthorn are 15th, Eagles are 16th and Hawthorn are 17th.
Of the "high tackle count" teams, only Sydney is having a good year, and that is being generous to them.
But if you look at tackle differential, you get a different story.
2012 we were 7th in the league
2013 we were 18th
2014 we were 14th
This year we are 16th
So, from this perspective, you could argue there is no concerted change this year and our tackle count differential under Lyon has simply reflected our general performance.
It's clear that the tackle differential doesn't correlate with the ladder in the same way as, say possessions do, probably because teams like Melbourne, Brisbane and Carlton have low differentials on the back of poor general pressure. But given this year West Coast is 18th on the tackle differential, along with us being 16th (while Sydney are 1st in the league) it does indicate something.