I would say it is about as useful as a knight being able to procure wine. It is, as you say, purely a personal talent.

[He says it with a faint chuckle, and takes another sip of his wine.]

I am one who is fascinated by many topics, and as such, I have a smattering of trivial knowledge about many different things. Though I may not claim to be an expert, I find that having such knowledge can be quite useful at times.