Thats kinda what I think too. My '72 UO-8 brought big(relatively speaking) money parted out. The '81 Miyata 1000 I got for a song sold for over $650 even though it did not have the correct factory gruppe so it's evident that people even now are willing to put up good money for vintage steel.
Even the entry level '88 Fuji Absolute I had recently sold for over $180. Now, I have only recently been in the hobby as a purveyor and after many years building hot rods, I know quality steel when I see it. Fit and finish is evident when you know what to look for. Over the last few months, studying bikes and the various production methods as well as watching sales and auctions I see the market is generally in a upswing price wise. As the availability of the '70 steel dwindles the newer bikes will only catch more fire.
I recently was lucky to acquire another pristine mid 80's Fuji. and though I enjoy the market end of this hobby I have decided that I will not let this one go. The fact that it fits me to a tee is a real factor in the decision to keep it, I also believe that financially the small windfall I could recoup now will be far out weighed by the future value IMHO