Here's a nice tip to allow users to quickly AB alternative plug-in chains in Pro Tools. It's very simple but the best ideas tend to be simple...
Shift + Number Shortcuts
There were a number of really useful shortcuts introduced in Pro Tools 11 which revolved around bypassing and muting plug-ins and sends in the Pro Tools mixer using the shift key. To toggle bypass for all plug-ins in inserts A-E use Shift+2, to toggle bypass on inserts F-J use Shift+3. The important bit of this tip is that is you start with A-E or F-J bypassed and the other set of inserts enabled then by hitting Shift+2 and Shift+3 together then as one set is bypassed the other is enabled allowing AB comparison on all selected tracks.
Free Tutorial Video
Watch the short video demonstration to see this technique in action.