nope,alertness dosn't increase your range .the perception stat gives you a base for these factors, the alertness skill will improve these factors.it works like barter and CH.
Alertness will be a passive skill, it will affect:-sneakers detection-traps detection-steal detection-start position in RE
So basically all PvP chars have to go weapon+alertness+sneak/FA
sneaking has been nerfed to the point of absurd, so implementing a special skill, that would give you a bonus to detecting sneakers, seems pointless.
all crafters are going to get screwed by sneak ninjas once again?
i think that the author has made a topic for his current character to be better