There are other ways to outline your art selectively (thus not using one single-colored outline). Why is the capcom-broken one the only one that's called sel-out?
Because that's what it meant when defined by its creators.
The point is to demystify, not to mystify. When people ask what selout is, we can give them links to threads, that's fine. If people ask what is a good way to outline their sprites, then we may help by explaining line width and light variation and etc etc etc without resorting to made-up-technique-names that further mystify, and by stressing that the better ways to outline one's work are relative and follow from good general artistic practices, not some strange pixeller-only-language.
'techniques' must be destroyed. Someone looking at Symphony of the Night and saying 'wow this style is rad, I bet they have specific techniques they used to get this result' probably hurts their artistic growth more than it helps. Fool's errands are popular because they seem to suggest shortcuts to artistic ability. "Learn selout and your sprites will become much better". This is meaningless and should die. "Learn art fundaments and your sprites, along with the rest of your art, will become better". This should be promoted. Dithering is a technique. Anti-alias is a technique. Banding is a discernible effect that should be talked about to much greater length. Selout is a byproduct of some bigger artistic decision that younger artists should face up to, not just look at the end result and pick selectively.