Hi, George,
The issue of "market price" vs "intrinsic value" is one that is of great, great interest to me (I'm an economics academic, trained in quantitative analysis but gave it all up when markets and especially individuals generally act "irrationally" and commentators would change their rationales and analysis as quickly as the shifting tides and sands..."the markets went up because Kim JI farted..." then the next day "the markets went up because Kim JI didn't fart today...") and a large part of ThePuristS and now PuristSPro was dedicated to shining the light on "intrinsic value" to counterbalance the often banal and self serving endless monkey chatter about "this is better, see, look at the auction prices!"
That said, I agree that poor overall average quality SHOULDN'T retain value.
Q: please define "quality"
Q: what are your perceptions of "value retention"? are you talking percentages, or nominal dollars?
You mention competent and skilled mechanics, you forget honest too...that noted, do you think the 959 can be serviced by the average Porsche mechanic? I have a bit of experience in the Porsche world (though certainly not as much as many others) - there are quite a number of incompetent and overpriced "Porsche specialists" who charge 3-10x the labour rate and 2-5x the price for the same VW part...it's a slippery slope, for sure, just like Citizen vs Grand Seiko vs Omega / Rolex vs PP/AP/VC/Lange vs Dufour / Voutilainen...
I happen to know a few competent and skilled Lamborghini (and Ferrari, Koenigsegg, Bugatti, et al) mechanics, certainly as many as competent 959 mechanics.
I'm not disagreeing with your main points, just would like to be careful to avoid dangers of generalizations and unexplicated assumptions and sub-conscious biases...
Cheer,
TM