One of the other shitty things about the shocks up front is that they have to come off to be adjusted (not the ones in the rear though). Although I’m working on a plan to get around that one.
If I remember Koni's literature correctly, not only do you need access to the top of the piston shaft, but the shock must be fully compressed as well.
It doubt it would be all
that hard to find a way to access the top of the shock while still mounted to the car. Heck for you coil-over guys it's probably no effort at all.
But fully compressing it? Even if one could manage to fully compress the front springs on-car, I don't think the shock is fully compressed at this point.