Personally I've always found this sort of thing to be one of the most selfish things any role-player can do with their character. Granted, there's nothing stopping anybody from doing it but many role-players will no doubt react poorly to it and seek to distance themselves from whoever embraces such a plot point.
Touching upon any major NPC outside of fan-fiction is dodgy because it essentially places one's character on a pretty lofty pedestal far above many others. Even if one strives to play their character as influential and well connected...that can easily be achieved without claiming to have brushed shoulders with major lore figures.
In my experience it's the sort of thing that just encourages a rather dubious arms race or for a character to be given an unwarranted amount of IC and OOC attention. Again, though, ultimately people can do what they want - they just need to accept that if they take liberties then they'll be called out on those liberties if they're too bold.
Touching upon any major NPC outside of fan-fiction is dodgy because it essentially places one's character on a pretty lofty pedestal far above many others. Even if one strives to play their character as influential and well connected...that can easily be achieved without claiming to have brushed shoulders with major lore figures.
In my experience it's the sort of thing that just encourages a rather dubious arms race or for a character to be given an unwarranted amount of IC and OOC attention. Again, though, ultimately people can do what they want - they just need to accept that if they take liberties then they'll be called out on those liberties if they're too bold.