I agree. I know what you're saying, the ww brass and percussion are really knock out rather than the strings being below par they are simply not *as good* as the others for realism *on their own and dry*, but I think this is because of the mix not VSL. Somebody wrote an interesting thread in the mixing forum about this and I think there was something in it, a modern orchestral recording has the directional mic's close to the instruments, - this is done in VSL so we ignore that stage, but what is left then is the room mics - so we use IR verb for that, but there are always a number of room mics, spillage and delay for sound to travel to different points, and I think it is this affect that often creates more air and warmth and more of a real sounding string. If you put the strings in a dry room and played them - you'd get VSL strings. So what I'm saying is that I don't think there is any inherent flaw in the recording or production of the VSL strings - they're true to their purpose and excellent at that. I think it's now down to performance, programming and more than those two in terms of texture timbre, ambience etc, the mix. I think MIR will go very far in dealing with this issue but I think there is still a lot that can be done with existing tools.
I think part of the reason the strings sound different in a real recording is because it is a larger space ensemble in terms of square meters and that is always going to generate a different response at the room mic's than a single instrument, percussion instrument or even a small ensemble like 3 trumpets for example. They cover less physical space and accoustically project a different image than 14 violin players where different players are going to hit different mics at different times.
I think part of the reason the strings sound different in a real recording is because it is a larger space ensemble in terms of square meters and that is always going to generate a different response at the room mic's than a single instrument, percussion instrument or even a small ensemble like 3 trumpets for example. They cover less physical space and accoustically project a different image than 14 violin players where different players are going to hit different mics at different times.