I agree, but your argument is more solid than this.I still think the FAQ is open to interpretation, and doesn't necessarily instruct you to use all the rules on page 281 when a target is hidden.
Even if one does use all the rules, it does not mean at the exclusion of the other existing and more obvious rules regarding stealth, perception, cover, and concealment. So you're right in either case.
Yes, or any of the numerous other ways to break stealth (moving, light, etc.)A Stealth check that is opposed successfully by a higher Perception check (whether passive or active) is a failed Stealth check, so the moment someone's active Perception check beats their opponent's Stealth check, he ceases to be Hidden from them.
If they fail to beat his Stealth check via any of the Perception checks they've employed, yet still want to attack him, then you refer to page 281 - specifically, the last two sections, detailing that you can either pick a square to make a ranged attack against, taking a -5 penalty to the roll even if you choose correctly, or else make a Close or Area attack encompassing the area you believe he is in, in which case you take no penalty to your attack roll if he is present.
I agree, but both of these rules are also already in the standard text and so if anything it's simply a refresher.
Someone you can't see already has total concealment and you have a -5 to hit, that's from the concealment rules. Cover and concealment rules also spell out the vulnerabilities to area/close attacks.
So the side bar is more of a helpful organization of the relevant rules for the specific case of total concealment from sources not dependant on stealth, coupled with stealth. The last two happen to be the same for both stealth and the side-bar specific case.