I think you should probably just quit talking to me. I'm pretty sure I understand Si better than you do. Functions are attitudes, they are ways of seeing the world, they aren't things like "memory" and Si is not "a matching function."
I didn't realize you were like this, until now.
You're doing this just because you said you think I'm an ENFP, in fact you announced it, like you know, and questioned why I thought I had Se instead of Ne, and I expressed my opinion that I don't necessarily feel sure you're an INTJ, so we probably shouldn't just have this conversation.
But you persisted. And now you're mad. And I never even said you were an ISTJ, just FTR. You're pissed off that I questioned your type.
But you questioned mine first.
This isn't about my understanding of Si. You've made it about you.