The point concerning portamento is that it is as variable as taste, but at the same time conditioned by what is possible. It is often impossible to do a full slide, so players will "fake" such a thing if the conductor or score demands it, with a partial slide to the next fingering change. However, the danger with samples (as far as realistic presentation goes which is not very far with me as I don't really care) is that the sampled portamento is recorded in isolation, and allows far more sliding than would be possible in a normal musical context.
This brings up something that I think is of crucial importance, but always ignored. The "purity" of sampled sounds. A line played live is extremely impure - not as everyone immediately is thinking in mere intonation - but also in dynamic level, style, portamento, legato, staccato, etc. etc. etc. Any number of expressive elements. There is variation at all times in any live orchestral performance. But with samples, everything is "pure" - especially with extremely detailed and perfectly recorded samples like VSL. For example, go to ff espressivo violins. Every single note is exactly that. But if you listen to any live played line of music, only a few will be that way, even though the score says "ff espress." And this applies to ALL ASPECTS of expression. So anyway, the point I was thinking about is how crucial it is to totally mess up the "purity" of ANY aspect of MIDI you are using in order to get a natural sounding performance. And this is something everyone resists, because of natural or trained musicianship.
