We definitely call two different things Si then. As I said, my version of it "perceives external information in form of sensations evoked by ongoing events".
It seems detached enough to me. I hear @Pookie etc say these things all day.It's a SEI quote. And I don't think Ni-egos would say such a thing. Ni is more detached.
I looked a bit but it didn't really help much.Did you check the examples (youtube vids)? I'm static as you point out, so it's obvious that I'm not the best at explaining the dynamics of Si, but the videos are good examples of what I try to explain.
Anyway. Can you say more on the stability thing where I asked: In what sense? How is this different from Ij temperament's stable reality?