Ok, Im at level 4/5 of this aa (not quite sure why I decided it would be useful...pvp server so actually seeing players sooner rather than later about only advantage...) but cant really find any information on how much difference it makes.

Increases skill cap by 10 per level, but what does this equate to in terms of distance ingame ? I should have thought at start and found a named and seen how much further I could track it from on each level, but I didn´t.....has anyone ?

i got it maxed and i have notsee any dif in it my self may be gain a few yards is all my self i think it was a waist of an aa but thats just me

I am not sure if this really helps but if you know Anguish I couldn't track the last 3 aug mobs from Vilria the Keeper's (riftseeker aug mob) position. With the AAs I can track the furthest, First Lieutenant Minas, from before her position.

I got this while I was still doing PoP content, it made the difference in being able to tell if the Rathe Council was up, or not from PoEB zone line.

i notice a significant difference in the amount of tracking i can do ...
unless its KATTA, i can track anywhere in zone from 2 diff spots ... in any zone