This thread is depressing. I (and perhaps millions of LR users) want to dump LR for PM plus. Kirk Baker seems intent on saying "you guys got no problem," and seems to have signed off.
My suggestion/request would be for Kirk (or somebody at Camera Bits) to create a "toy" LR catalog with maybe 20-30 images. Then, like LR users do, start adding some keywords that are meaningful, some flat and at least a few sets of Hierarchical key words. Then take this to PM plus and see what he/she makes of it. Maybe even change/add a keyword, then round trip it back to LR? >> Proof of concept!! Say it loud on a video!
If they do this with the current release, would the PM Keyword list look like the user's LR keyword list? No, not close.
In my case, with my large LR database, many keywords (flat and in hierarchical in LR did not show up in PM+. In LR I saved and saved and saved to the images. Still not in PM+. The keywords in LR that did not show up in PM+ ALL showed up in PS, Bridge, and XnviewMP. What??!! Lots of possible why's I guess, but this stopped me in my tracks, even before this duplication mess PM+ creates.
Camera Bits, please find a way, perhaps even with destructive options, that "make it so" as the great Captain Kirk said. If you did a video with this toy LR database and showed the lightroom Keyword list, then the export to PM+, and its keyword list, this would lay down things firmly and end this discussion. And/or, maybe Camera Bits can give some definitive guidelines telling LR users how to prep their LR keyword list to make this easier/better?
Camera Bits, there are millions of potential customers waiting to see if you hear their cry! Please try to help me/them more successfully cross this LR/PM+ bridge.
FWIW, I sent this equivalent message to Camera Bits in a support email exchange, and have gotten no reply or comment. Camera Bits appears to be still joined too much at the hip with their traditional customers who do not give a rip about translating a large LR database with complex keyword sets that evolve over time.