Provenance and parts values

Beautifully presented and beautifully presented. Not my mate's Clan but a very fine example nonetheless. Have you noticed how most Vintage Things are worth more as the total of their parts? It seems to be the opposite of gestalt , where some things are worth more than the sum of their parts. I was talking to a friend the other day who owns a very nice Clan Crusader, probably the nicest Clan Crusader you've ever seen. It's all set up for rallying with a big bore engine, twin 40s on the right manifold, a very rare and strong gearbox and - perhaps best of all - a very lightweight shell. He's considering selling it because he has a growing family and won't get to use it properly for a while. However, having assembled all these glorious bits to create what could be the ultimate Clan, he's faced with the prospect of breaking it up because the sum total of the parts is £15,000 and nobody would ever spend that on a Clan. But they would spend £5-6k on the engine, ...