Apologies for reviving such an old thread, but I think this is important info for people coming here from google:
The localization dashboard WILL NOT find your string table unless you use the macro. If you want to localize your c++ defined string table, you have to use the macro.
…which brings back to the string literals being a massive PIA, which is what I’m currently banging my head against 
But you can see the scraping logic for yourself in GatherTextFromSourceCommandlet.cpp - that macro functions as a flag for the text gatherer to find the table. No macro, no localization.