There is a solution to USAF's lack of ability to retain technical knowledge, and that's to use the Warrant Officer ranks that got dropped back in the 1950's. These not-quite-officers were supposed to be technical experts in their field, and were not in the chain of command.
The other thing, which I pointed out back in the CyberWarfare thread, was that Airmen get promoted by passing skill tests. The tests get prepared far in advance, which means what you're being tested on is ancient history, so far as technical knowledge is concerned. Should be easy to pass, right? Except it's probably stuff you haven't worked with for a year or more, so you aren't going to do so well.