Yes, the Discovery ZF gearbox also suffers excessive line pressures in the 'A' clutch-pack if revved in neutral/park; but ONLY when line pressure remains from a recent gear selection (e.g: not likely to do much harm if revved first thing in the morning; before selecting a gear).
Smoke testing a diesel for an MOT test could potentially destroy a ZF transmission....the simple fix is to drill a small bleed-off hole in the piston casing; but why didn`t the manufacturer do it? :-?
Interesting, I wonder how many boxes have been damage by MOT testing etc. What age discovery's had the above autoboxes in? I'm thinking about buying an old Range Rover, I assume these will have the same boxes in as a Discovery?
Personally, I rarely rev the car in P/N unless there's a valid reason to, such as checking the operation of the dual ram intake valves and when I had a misfire a while back. Well, besides once when I had the exhausts removed from the cats back... you just have to wake the street up!
Yes putting the car into a gear when revving is going to cause problems and is a big no-no.