First, do yourself a favor and go to the Hydraulics Pages on Marinus Rijkers' Silver Shadow Website
and read through them and watch the animations. It's really critical that you understand how the system as a whole works (although you could ignore the height control part for the time being).
There is no real "brake feel" on the pedal of a Rolls-Royce other than what's provided by the return spring. All applying the brake does is to open a valve.
If he's got no pressure right off the bat for both systems and it never accumulates then I'd suspect failure of both brake pumps, but this seems to be a highly improbable circumstance.
Search for posts I've made in the past. I believe I put up the fairly comprehensive set of diagnostic steps to help you to determine where the failure in the hydraulic/braking system might be.
Since you're dealing with a Shadow II bleeding the braking system should be quite easy. There is no master cylinder to worry about and the way this system works it's constantly supplying its own pressure. Download my easy brake flush and bleed instructions
for further guidance.
When is the last time the brake reservoir was opened and examined? When was the last time for a full system flush and fill? Is the car using RR363 only? You could have tons of crud in the reservoir blocking the filter screens (or worse, the filter screens could have collapsed and the crud is now clogging the gravity feeds to the pumps). These cars need to have their brake/hydraulic system completely flushed & filled once every two years, at a minimum. Many were/are sadly neglected in this respect, and when you take the reservoir lid off and the baffles out you might be shocked what you find. These cars are designed to run only using RR363 fluid (though there are some using DOT3/DOT4 spiked with castor oil, but we won't go there). If the wrong fluid was being used, particularly straight DOT3 it can and will eventually cause excessive pump wear and failure. If, heaven forbid, someone put the later mineral oil hydraulic fluid into an RR363 system, and this has happened, the results are disasterous, with the mixture of fluids turning gelatinous and fouling the whole system.