Their point was that "familiarity" apparently means different things for different people :P Someone using linalg in computer graphics applications may say they're familiar with it even though they've never heard the term "eigenvector". I'm not actually sure about what you mean – how does repeated multiplication reveal eigenvectors?

My first sentence was in jest. I've used LA for various things, but haven't had many dealings with eigenvectors. So that information was genuinely new to me.

My expression of gratitude was sincere.

You're doing this multiple times, but it's can only mean "It Is" or "It Has".