The Sync in A/B works off the timeline of the DAW, so in Pro-Tools as long as the reference track starts at Bar 0 of your session everything syncs great. Given the nature of Montage Timeline, you can’t really get it to sync anything but the first track in the montage. So more accurately the Sync does work it, it’s just the nature of the sync that doesn’t fit Wavelab’s format.
It’s still great for referencing to commercial releases as it has lots of loop/marker functionality. The level match function works well too you just have to select sections with similar intensity while level matching.
Smart Bypass on the master section is superior IMHO but I agree with you notes in the video about the Master Section (I have on more than one occasion lost a tracks plug-in chain by forgetting to save it) so am looking at moving to something similar to your Montage only based work flow.