Okay so lets assume you are not trolling and making an honest point: it is still a bad one. Bo Davis is someone you kill to have on your staff and any DC who wouldn't want him is an actual fucking retard we should never hire anyway. If we had delayed his hiring by even days he would have ended up at any of the dozens of other places in college and the NFL killing to have him. Joseph was a similar deal; either snatch him then or miss out. He wasn't going to be available by the title game let alone now when we still haven't made the DC hire.
The only other member of the defensive staff, and the only one that is arguably a questionable hire, is Gideon. In retrospect had we known Banks was coming it is likely we would not have pressed so hard to get him as quickly as we did but he had plenty of offers out there and likely would not have been available. Considered a rising star, fuck tons of connections with HS coaches (something Texas badly needs to repair) and a lot of people our decision makers respect consider him basically 'the next great up and coming defensive coach'. Plus you really need at least one guy on staff who actually knows what its like to be a student at the program itself and he fits that bill as well.
TLDR You have to be actually fucking retarded to take issue with Bo Davis or Joseph hires, DC in place or not, and Gideon made a ton of sense at the time (and still does) as well. DC can still bring along one underling.