Thanks for the replies, some have been very insightful, yet it has the inevitability of more questions. I suppose I shouldn't of posted them all in one topic as they're rather big subjects in there own right.
John, I agree with alot of what you've said. Quality materials and time would of played a major role, yet it leaves me wondering about the quality of Shinsakuto as they have the materials and all the time in the world given the ease of modern life in comparison. Maybe it is just waiting for a particularly talented Kaji, but as I have seen with other skills that are no longer needed to the extent they once were with traditional tools such as stone masonry, there's a massive void between then and modern practitioners.
Paul, I must yield that the first question was a poor choice. It may of been more prudent to ask something more specific such as the merits of different Kissaki, but from my understanding these things changed alot due to different needs for different periods, so it's hard to put my finger on something that has remained constant yet there's a noticeable difference between a good and simply average blade except overall build quality which would require volumes :D
It could be argued that the differences becoming blurred could improve the overall manufacture with more uniformity towards a more ideal product, this clearly wasn't the case but it is interesting to me as that has happened with many different things. I suppose that would also destroy the "art" aspect thast is so varied and wonderful, much like the pop music I so detest that now all sounds the same but sells.