I thought this was a cool article explaining in part Mac's D principles...
“Macdonald teaches blitz patterns,” Nguyen said. “So he’s teaching, ‘OK, instead of this linebacker blitzing the A-gap, this player has to blitz in this A-gap. And if this player blitzes this A-gap, then this player on the weak side has to drop.’ Everybody kind of knows what each other is doing, so you could change up the front and you could change up which player is doing which job. … They’re just really learning the blitz as a whole, and that way everybody’s interchangeable.
“For the defense, it’s very inexpensive,” he added, “because we’re learning this one pressure pattern and they could run it from 10 different presentations. So for the offense, they have to prepare for 10 different blitzes potentially, whereas the defense is like, ‘We’re just running this one thing out of different presentations, because the way we learned it, we could easily switch things up.'”
sports.mynorthwest.com
“Macdonald teaches blitz patterns,” Nguyen said. “So he’s teaching, ‘OK, instead of this linebacker blitzing the A-gap, this player has to blitz in this A-gap. And if this player blitzes this A-gap, then this player on the weak side has to drop.’ Everybody kind of knows what each other is doing, so you could change up the front and you could change up which player is doing which job. … They’re just really learning the blitz as a whole, and that way everybody’s interchangeable.
“For the defense, it’s very inexpensive,” he added, “because we’re learning this one pressure pattern and they could run it from 10 different presentations. So for the offense, they have to prepare for 10 different blitzes potentially, whereas the defense is like, ‘We’re just running this one thing out of different presentations, because the way we learned it, we could easily switch things up.'”

What separates new Seattle Seahawks coach Mike Macdonald?
The Athletic's Ted Nguyen delved into how new Seattle Seahawks coach Mike Macdonald is setting a trend for defenses across the NFL.
