I have this edge on my list, although I can't fathom it having any use for me (felar, ranger).

Not every edge is super useful for every character that can pick it.

Yeah, my point just was... I already have darkvision and cave vision, and the helpfile explicitly says it just helps with sharpen sight (which I imagine to do one or both of above, I've never had it myself). Unless it also helps with scan ranges or other vision-sharpening skills like acute vision, I don't see why it should be available to my combo since it would do absolutely nothing (again, just going by the helpfile, here!)