Well, pragmatically I think there is little demand for making MIDI Channel the message to control articulation switching in Vienna Instruments. I have no idea how much work it would entail but I never heard anyone bring it up before.
George, with respect, you're missing out on quite a lot by being dogmatic. If you're sticking with notation as the [single] way to sequencing maybe you're not as interested in the same things as most everybody here, though. Already said, 'I have a bit more than 16 articulations loaded typically', etc. The score doesn't play itself. Though there is one guy that's posted here that makes fairly convincing music strictly from notation, it's anomalous.
Sticking with PLAY interface and eschewing VI, VI Pro particularly out of this one thing is a bit jarring to people that are interested in it.
As I understand it, Orchestral Tools moved away from their Articulation Performer interface for their strings, stating at VI Control their preference for the old ways (a track for each articulation). IE: instead of crossfading in one instance, overlapping of separate events. Strange argument.