Given that Dumbledore knew the DADA position was cursed not to last more than 1 year, couldn't he just hire DADA professors with a 1-year, non-renewable, contract?
I mean, he knew that wasn't going to last, so if he pretended to hire them "for life", the curse would automatically have made something happen to that teacher, possibly something bad.
However, if they were just hired with a 1-year contract, they still had to go after 1 year, but at least nothing bad would happen to them as the result of the curse. I.e. the curse wouldn't trigger, since they would have gone anyway before it had to trigger.
I only care about in-universe explanations, though I suppose that, sadly, there isn't one.