NO. It's not an INFP thing, or an ISTJ thing, or related to type at all.
I think it's VERY important to be aware of the limits of MBTI. People put way too much emphasis on it when trying to relate it to general abilities.
I'm an INFP. No doubt about that.
I'm good at languages.
I'm good at math.
I'm very good at music.
Either I'm not an INFP (because my mathematic abilities don't fit the stereotype of the bleedingheart irrational, emotional INFP), or the steroetypes are wrong.
Assuming that someone's type gives you a glimpse into their faculties is truly nonsense.
But what the fuck do I know about it? I'm just an INFP.