Hi Robert,
I think you misunderstand the point I was trying to make .. that for most amateurs the free downloadable Gray classification atlas probably contains sufficient information for MK classification. Gray himself says it is synopsis of the 600 page G&C book. Compared to having to pay ~AUD100 for G&C I consider 'free' a great bargain if it does the job.
I doubt I would be surprised at what advanced amateurs are capable of, having just returned from this weekend's NACAA Conference at Sydney university where advanced papers were presented. I also made a presentation there showing the professional quality spectroscopy SASER amateurs do for pros worldwide (you can see our work at
http://saser.wholemeal.co.nz/). A paper that used a lot of our spectra was published by ApJ in January (
http://arxiv.org/abs/1601.03396) ... I'm the third listed author. Ken (Merlin66) is also a SASER member, so I think we do have some understanding of amateur spectroscopy and stellar classification.