I strongly disagree with this statement. And will give it a big duh. Most coaches in the NFL hire people they know, feel comfortable with, know their system, know their work ethic, trust, and believe in. And they hire those people knowing that their job will be on the line if those people fail. There is a reason why they call it the coaches' fraternity because that is how close you have to be to make sure everyone's on the same page.
Working with people who know how you like to do things, and that you know already, helps you hit the ground running. You have more people who understand your shorthand.
Sometimes hiring your buds helps, and sometimes it doesn't. It is like anything in life--but it ain't unusual having the good ol' boy network saying who you hire because the reality of NFL coaching is that you spend tons of effort and energy and time working with these people and you want them to be people that you trust, like and respect, and know that you are on the same page.
The Capers/Palmer matchup was a bad one. Well regarded HC and a well regarded OC--didn't mesh philosophically.
This situation reminds me of a satellite office I used to work in as low paid minion. It was a national company that was trying to put together a smaller office in a city that they had never had an office in. And they hired various superstar employees from that city that had never worked together before. And it turned out to be among the most dysfunctional places I ever worked--kinda creepy, and nobody really worked well together. I got out of there as soon as I could, and after a few years, they closed that office down.
As for the Seahawk/Steeler way of keeping coaches through tough times, that's hard to do too. Everybody WANTS to do it, it is the ideal, but you stare at enough non-good records, and it is hard to do it. That being said, Bob McNair has often said how much he admires the Steelers organization, and you could tell how much it pained him that Capers did not work out. (BTW, and completely off-point, I find Green Bay's off-season coaching changes baffling).