Given the screenshot from Fafzor, I'd assume they count as still fogged. Which makes this a strange advancement. From what was said before, I assume that you will strictly get to see the first n recipes. If one of them is a bonus reward, you will most likely not get another revealed. If one is semi-fogged, a Fog Buster will still fully unveil it which will count as one territory.
Yes, these are all assumptions, but I don't like what that would mean for their usefulness.
I'd invest my AP in so many upgrades before I go for a crafter visibility. At the end all the upgrades are good, but some upgrades are just better. Maybe starting from the 7th ascension visibilities are worth it
Maybe after I have started not getting Fogbusters from levels anymore
6-12 visible items won't do much. If you invest go to the max. And for maxing mines+recipes+crafters+markets you'll need AP that you can better invest somewhere else. The only exception for me would be Mercenary Camp Visibility
Keep in mind that you can get fog busters via the coin wheel even after you used up the powers on the map (i.e. collected them twice).
After 2nd/3rd ascension many other advancements are still better than the visibility advancements imo (this excludes merc camp visibility which is indeed useful if you strongly rely on mercs).