Although the circumstances were different -- Garrett was more or less encouraged to do so by Dallas Cowboys owner Jerry Jones after the 2012 season, while McCarthy did it voluntarily -- both have joined the ranks of head coaches who don't call plays.
"I love the role that I have now," Garrett said Wednesday at the NFL scouting combine. "I love the structure of our staff now."
When McCarthy announced the change last week, he cited the current makeup of his coaching staff and the long-standing relationship that new playcaller Tom Clements, who was promoted to associate head coach, has with quarterback Aaron Rodgers as factors in his decision.
The move came less than a month after the Packers' collapse in the NFC Championship Game loss to the Seattle Seahawks, a game in which special teams and defensive breakdowns factored heavily in the outcome.
McCarthy, who had called plays since he was hired as the Packers' coach in 2006, now says he wants to be more involved in special teams and defense.
Still, the move was met with surprise in league circles given that the Packers' offense has ranked in the top 10 every year except 2013, when Rodgers missed half of the season because of his collarbone injury.
"Whatever they're doing there, they should keep doing it," Garrett said. "I trust Mike McCarthy. He's obviously one of the great coaches in this league and has been. They've been one of the best teams during his tenure as the head coach. He has a great instinct and feel for the game and his football team, and he's going to do what he thinks is best.
"I do think that it does allow you to really get more involved with the other parts of the football team. I spent a lot more time with the defense over the last 18 months than I had prior to that, and I just think that's good for your team when you're able to do that -- support your coaches, get a better feel for the players on that side of the ball. So that's worked for us. But trust me, I defer to Mike. He's done a fantastic job, and he'll make the right decision for the Packers."
McCarthy's decision left only 10 NFL head coaches who call plays. Eight of those are on the offensive side of the ball.
"Everybody will give you a different answer on that," said Kansas City Chiefs coach Andy Reid, who calls the offensive plays. "I think Mike feels that way now -- just from things that I've read, I haven't talked to him about it -- whatever he's decided to do will be the right thing. He's a pretty sharp guy. Heck of a head football coach. He's a great playcaller, too. But he obviously has confidence in Clements to do that and [offensive coordinator Edgar Bennett] to do that. He knows better than I do, the situation."
Reid also handed off play-calling duties at one point in his career with the Philadelphia Eagles. He turned things over to Marty Mornhinweg, who was the Eagles' offensive coordinator from 2006-12, but went back to calling plays when he was hired by the Chiefs in 2013.
"I had a guy that I had 100 percent trust in, so I had no problem doing that," Reid said. "And it worked."
The biggest difference for McCarthy might come on game day.
"When you're not having that direct responsibility, you do have a chance to get involved with other parts of your team during the game," Garrett said. "When I was calling plays as the head coach, I spent some time on the bench with Tony [Romo] and with the other guys talking about what we wanted to do. I talked on the headset with the guys upstairs ... while the defense was on the field. Didn't have to do that since I've been the head coach not calling the plays. So I think that's a positive thing. You're probably more tuned in to what's actually going on during the game at the particular time."