More like the moment you add a second Mutex in your app, ad-hoc handling and no policy to prevent deadlocks. The solutions are well known and I'm simply sad to

More like the moment you add a second Mutex in your app, ad-hoc handling and no policy to prevent deadlocks. The solutions are well known and I'm simply sad to see them far too little used. But in the case you insist in doing that (not using architectural solutions, some of which can be checked statically), yes of course runtime deadlock detection is a very valuable tool. I agree that it is even useful if you rely on policy but can't automatically check that they are respected.