I completely agree about coaching and the big difference it makes in philosophy and player confidence. The last coaching job was a joke.

However, just to be a bit fair to the defense from last season:
1. Look at all the new players brought in this year and the difference they're making (Campbell, Bouye, Church - none were on the team last year)
2. Cyprien is gone
3. Myles Jack barely even played last year.
4. Fowler was essentially a rookie last year (he looks better this season)
5. Yannick was a rookie (although he was good last year)
6. Ramsey was a rookie (although he was good last year,, but REALLY good this year)

I think the addition of key players this year, dropping Cyprien, and the extra year of experience for Ramsey, Fowler, Jack, Yannick have made as much difference in improvement from last season as the coaching change did. 

 Changing the coaches + improving the players is why we see a BIG improvement, IMO

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