re: Why did CBK think he could make it without a DLine coach when Lindsey left??

It’s a perfectly appropriate question and if you don’t think so, you haven’t thought about it much.
Medical emergencies happen and sometimes you need new personnel, particularly here, where Lindsey was totally incapacitated from conducting job duties.
We have a DL position coach b/c we need one, not b/c it’s a luxury.
And if House thought he and others could cover capably with no diminution in performance, what did they think after FSU? After Grambling’s first three series? After Arky?
Until fans and the media went berserk about this defense post OM, I cannot see anything House did.
We were not helpless after Lindsey’s August diagnosis. If we made any material adjustment, it is not apparent.