Click-clack I would however never buy me back, which is totally impractical. Precise (post-) rules is not possible because you are constantly added to the resistance.
Precise readjustment is necessary, for example in combination boilers where often does not occur immediately the full amount and not the final temperature of hot water.
At most, in Gästeklo where you want to patronize educationally water wasters instead teach them correct usage. So what for the more public or semi-public areas.
Note: If you have the handle of the faucet on the side rather than above, the rotation angle is not suitable (in such taps he would be offset 45 ° forward).