I set up a macro to do a quick A/B on a bunch of tracks by muting tracks by name with the PLE.
The macro looks like this:
Group A
Deactivate All Mute States
Process Project Logical Editor - Mute xx
Process Project Logical Editor - Mute xx
Process Project Logical Editor - Mute xx
Process Project Logical Editor - Mute xx
Group B
Deactivate All Mute States
Process Project Logical Editor - Mute xx
Process Project Logical Editor - Mute xx
Process Project Logical Editor - Mute xx
Process Project Logical Editor - Mute xx
But while muting group A, results in hearing group B only, as intended, when muting group B, a bunch of tracks in group A are silent. They are not muted on the track header and even if I solo them they are still silent. Only if I then ‘Deactivate All Solo and Mute States’ on the Tool Bar do they become audible again. Very odd 
This works fine with lots of GA tracks. But doesn’t work with lots of MIDI tracks going into VE Pro.