So, I have been using Galatine Prime as my primary melee since its' release, previously it was base Galatine. And while I killed A LOT prior to its' prime release, I have noticed that despite my best efforts to update my profile to say that Galatine Prime is my most used melee, it has not been updating in the way I thought:
https://steamcommunity.com/sharedfiles/filedetails/?id=3101118119 - here it shows how many kills (509,903) I have with the Weapon, and how much XP (148,830,050) it has earned.
https://steamcommunity.com/sharedfiles/filedetails/?id=3101118081- and here it shows that I have accumulated more to the total kills (509,994), but the XP total remains the same (148,830,050).
The only thing I can come up with is that I installed a focus lens onto my Galatine Prime. That's my best guess, but I don't know for sure.