That's an understandable and very honest description @ChosenOne, thank you for that

. When you first read the Si descriptions, you can think "wow that's the most boring function ever". But you could easily miss the point that this is indeed the most primordial function aswell.
There is that model, you prolly all know, from "human experience learning study" (ya, my english sucks

) when a kid touches a hot plate and finds out the plate is hot. It will touch the plate, no matter what until it found out the pain connected to touching it. Then it has learned.
I would postulate that a S dominant would be more prone to actually finding out what it feels like what is called "hot plate that gives you pain" and a N dominant would be more prone to imagining and therefore accepting the fact the plate is hot so dont touch it.
Both attitudes lead to problems that's for sure: The S dominant can get serious burns throughout life, while the N dominant could never actually experience life or worse be carried away mentally by the means of imagination into a reality that does not really exist.
In addition to what TCO said:
I myself had problems grasping the nature of Si and I admit I havent really grasped it so far. Maybe that's because I am waiting for some crucial epiphany to come along with the understanding of the function and totally miss the point that it is just as basic as the description of N is. With the difference that of course, if you are a N you can imagine a whole lotta shit in your N function, ranging from having the ability to predict the future to astral projecting oneself into starting to see the world in only colours, which are either indicators for a "good" person or a "bad" person

.
But and now comes my point, I generalized the whole thing a bit. I thought, according to mbti model the whole world can be divided into Si-Ne and Se-Ni types (not counting function order now, it's only a generalisation).
Under that premisse I started to watch my surroundings to see what people do differently. And I found a 1st very intresting difference: there are 3 persons involved, me (entp), my girl (infj) and my mom (isfj).
My mom has the unbeaten knack to know where every little item that ever went into our house is. She is like an archivist. She doesnt conciously remember it, like having a list in her head, when I asked her to find me something, she has hunches on where it could be and if you then wait around 10 minutes to 7 days she will come up with the item you wanted to find.
It's a knack really. Now to me: I am not so good at that. But I think I do understand the basics. When I search for something, I remember sensory experience where I saw it the last time. Most of the times this is visual rememberance showing a place in my head where the item was. I am tho not very good to imagine pictures in my head, so this is pretty N influenced in my head and I will start connecting random facts having blurry pictures and ideas, often doing the search based on things I saw that can lay up to 10 years in the past and therefore not making the search successful cause I am mixing up time frames, places and different experience from the past. Even can go so far that I mix other peoples opinions I once heard or other peoples positions into my own and become very weird.
Well nevertheless, my home and my computer are a mess to an outsider. If someone asks me for something, I will nevertheless find it, somehow, one day. My mom is better at that, but nevertheless I do aproach things the same way.
Now comes the comparison to my INFJ: she makes lists for everything. She has a full statistical book in which everything one could bring in order is prolly ordered. So if she needs something, she opens her book and there lies the answer. And why is that ? Cause her memory of the past is that ultimately shitty, if you drive with her through a foreign town once and then drop her off at the location, leaving her there, telling her to find home on her own again, you never gonna see her again.
I am not sure if that special idea does correlate with all Si-Ne and Se-Ni types. But, there is a difference in the approach concerning said things and it may be, may be not have got to do with Perceiving functions.