No way, even with your expert setting up would I want to park a GV including yours on Saltburn or Statithes bank. The 'rolling back' built into the design of the top-hat was only ever envisaged to stop cars coming off drives outside a house and into a road of traffic not 1:4 & 1:3.

 

Just leave it in gear if parked on a steep incline, that way you get 4 wheel braking :-)

 

Since the parking brake works "somewhat decent" rolling backwards, and you can always use the gears to keep the voyager in place when parking, the main problem would be being in a traffic jam moving downhill

Although I must add today I almost hit a car waiting behind me trying to get out of an underground parking garage with a very steep exit during rush-hour..
I just missed that last "click" of the lever

 

A traffic jam moving downhill........ just use the foot brake n roll with the flow ? Who ever uses the handbrake goin downhill in traffic ?

Seriously... don't see this handbrake thing as a real problem ?

 

You have a point rolling downhill.

The poor handbrake performance is not a big/real problem but I can imagine if your strive for perfection the poor design of the brake is a pain in the a$$.
And in most countries it IS a problem passing the MOT.
In The Netherlands we call that periodic test APK and I had a big problem passing the handbrake test, but I did after some adjusting.