Thanks Donford
Although I've got a Grade C page optimisation score, I've just checked and in the UK our site appears on page 1 rank 1 for Vintage Chanel bags (Google) which did surprise me somewhat.
Our products are transient, staying around for 2-6 weeks on average. Each item is unique, so no real time to build links to products / page authority etc. So I think your right to mention concentrating on the category SEO rather than the products (especially for us).
But... if I search for a more long tail term 'vintage chanel pink shoulder bag' we also appear page 1, rank 1, so I feel a bit like 'if it ain't broke, don't fix it'.
The link to previous discussions isn't specifically about Ecommerce sites. I've checked a few competitors and they use 'Vintage' too, not that this means it is correct.
However I'm always open to change, my gut (not factual) feeling is that dropping Vintage from products would affect adversely the longer tailed search mentioned 'vintage chanel pink shoulder bag'.