>there is no real-time, as you compose way to implement the trick. The only way to do it is at rendering.
DaddyO, here's how I would make the 'transpose trick' work in real time using two MIDI tracks in Logic: Record a 'pitch wheel max' movement (no notes) on MIDI track #1, delete all but the maximum PB value from the event list (or whatever your DAW calls it) and extend the MIDI region manually (ie by dragging its right hand edge) to a large amount of bars.
Set MIDI track #2 to transpose -2: that will transpose all incoming MIDI notes down a tone in real time. Put MIDI track #2 in 'record ready', start playback from the top and play along: the PB you recorded on MIDI track #1 will bend the samples' pitch up a tone in real time for as long as the track is playing, and as you play along at concert pitch through MIDI track #2 you'll hear your second violin part at the right pitch (but using a different set of samples) in real time.
@EP >as this is apparently how the string libraries work, I love to see VSL
implement a global function that would take care of the pitch bend and
transposition for an entire preset. The users should not need tinkering
around with their sequencer / notation software to set up the second
violin section.
VSL don't encourage this way of using their libraries because pitch bend makes the sound a little less real - they suggest other methods, such as using a different, similar-sounding articulation, or giving the nominal first and second violins a different reverb / panning treatment. As I said earlier, this only becomes an issue anyway when seconds and firsts play a *unison* note, and even then the phase-related audio artefact that *might* occur (and it might not, if the notes in question were played a few ticks apart) doesn't sound too bad - it's not like a horrible glitch, and you probably won't hear it in a full arrangement.