I just found that hiring unusual, like Chip didn't have connections in the league.
Chip Kelly and Pete have been around each other for a long time. At Oregon they coached against each other since 2007 when he was OC. In 2009 he got promoted to HC. In addition to that we had to face off against him twice in 2016 when he was SF's head coach. He also coached against him in 2014 when he was the HC of the Eagles.
In addition Carroll was involved very heavily in the Seahawks front office. He was on the front line when it came to scouting and player acquisition. He also talked to Chip Kelly quite a bit about Zach Chardonnet. This isn't all, he got to see how UCLA used Zach in their offense and got to see first hand how they structured things. Who knows who else the Seahawks FO scouted from UCLA during Chips reign.
We cannot say that there is not connection here. Carroll has coached against Chip Kelly for years and he got to see what he did at Ohio and UCLA. His issue in the NFL was that his offense completed messed up the TOP and put his defenses in bad positions. Since UCLA and Ohio he completely changed his philosophy and style.
Chip also has made it known that he just wants to be an OC and he doesn't want an HC role in college or the NFL anymore. Carroll has had a lot of run ins with Chip in both his collegiate and NFL career. He's watched tons of tape on Chip in scouting and game prep and has gotten to see how he's evolved his offense, because what he did in the NFL and Oregon is completely different from what he did at UCLA and Ohio.
In fact, you could say that Pete is more well acquainted with Chip than he has been any of his OC's that he hired as the Hawks OC. The move to hire him as HC actually makes a lot of sense on paper, ESPECIALLY when you consider the fact that they came from similar backgrounds coming from college. There is a of crossover here. I think this was 100 percent a Pete move and it is exactly the type of thing he would do. Kelly's new style is also very much so aligned with what Carroll wants from an OC, plus it just so happened that Kelly made it known that he wanted an NFL OC gig.
Quite frankly I think Chip is the smartest OC hire Carroll has made in the NFL. Kelly was fishing for an OC job in the NFL and it just so happened that Carroll needed one. This isn't a strange hire at all considering how many run ins and now how the offensive strategy now more closely aligns with Carroll's philosophy. It just so happens that Kelly isn't interested in becoming an HC again and he just wants to do his thing on offense.
The more you look into it the more that you see that this is very much so not a strange pairing. I don't believe for one moment that anyone intervened in this hire.