The finger-tip hydraulic system

Did you know that your Mercedes 600 includes several hundred meters of hydraulic valves?
The switches and cylinders connected to those valves are mostly going to leak after about 30 years of operativeness.
Within each switch and cylinder are located a multitude of different rubber rings resp. grommets. These rubber seals are exposed to constantly changing environmental stress such as heat or chill - for this reason they become porous and therefore the inner resp. outer diameter of the rings changes.
If the inner diameter of a rubber seal which encloses a connecting valve increases to about 50%, the pressure of 175 bar within the hydraulic system isn't able anymore to press the grommet on the valve which would be necessary to keep the system leakproof.
So what has be done about this?
It's especially important that every rubber seal in a hydraulic switch or cylinder is going to be replaced so that the leakage is eliminated at it's origin.