Detail is precisely the word I would use to describe INTP memory. Ne does not denote a lack of detail, on the contrary I've found that my Ne brings in details that others completely overlook.
Ne does not notice detail. It notices patterns. This is precisely why "others" overlook what a Neer easily notices, because patterns are indirect representations of details.
Furthermore, tertiary Si remembers things in hindsight, and (often useless) details are very important to our memories. The way I understand it, Se translates to General but wider while Si is specific but narrow?
Extroversion/Introversion of Perceiving Functions determines the flow of perception. If Pe, then perception will rely around the objective. If Pi, then perception will rely around the person(subjective). Thus, Pe is limited by the objective criteria whereas Pi is independent. Thus, Se will be "enhanced" perception in a limited timeframe and situation(objective) but Si will be "consistent" perception relying on the experience of the individual(subjective).
Se and Si are both specific, it is what makes them "S" functions. What really determines their difference is what is said above. Although, because Se is an extroverted function, it will have the greater degree of specificity but only during that exact situational of perception. I guess you can say Si covers more because historical information is inherently "breadth of detail" whereas Se is "depth of situational detail". The thing is, with information, you can make Si focus on one subject and therefore produce the same "depth" of detail as Se. But it's not as situationally "handy" and "flexible" as Se.
Also bear in mind that the inferior function is all or nothing and is generally a weakness. If Holmes was using Se then it would be pretty useless in the inferior slot. However, in most interpretations (especially in the movie) he is shown to have social problems, which indicates an inferior Fe instead.
Inferior Functions does not necessarily mean ineptitude, it could also be about a "wacky obsession in details" such as in Holmes case. What the "Inferior Function Slot" essentially means is the least preferred behavioral inclination. Thus, the least used, thus, the weakest. The resulting "attitude"(frustration) towards the inferior function can either form an "antagonistic" (misanthropy in Inferior Fe) or an abnormally obsessive use of the function.
With Holmes, however, I see a significantly greater degree of Ni than Se. Sure, he notices some details but the overall methods of his deductions rely on connecting all those dots. I mean, you could get all those details and still be really confuzzled. I think that's where he is masterful, the creation of a complex and yet still valid possible "background/prediction" from the seemingly insignificant details. Introverted Intuition.
Aye, and also important to note, he notices instantly and in any situation. That needs to be said too. Anyone can see those details if they look for it hard enough. Holmes notices instantly, despite the direness of the situation he finds himself in. That has to be use of very good Se, and can't be simply 'mimicked' by types not able to use Se to such an extent.
Again, he notices the significance of those details because of his Ni. Does he notice any irrelevant information? Does he feel stimulated by simply "noticing" stuff without deduction? No, he does these things ultimately for the benefit of his dominant function.
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Of course, that's just my theory.