Good point about the lawyer lips. However, it might also be possible to mount them inside the forks...
And it depends on the forks: I have a set that I am planning to use on a set of
carbon trekking forks that have mudguard eyes which work fine with the current rim brakes, but would clash with disc brakes. As and when I switch to a BB7 disc brake, the plan is to attach these Q-clips to the mudguard eyes to effectively move the mudguard eyes rearwards to a more usable position.
How much effort would it have taken to add mudguard attachment points (i.e. M5 threaded holes, hardly rocket science) to the forks at the design stage, on the inside of the forks just above the disc brake (around where everyone has attached P-clips in the photos below) ?
Minimal. And yet few manufacturers actually do this.