Ripple said:
That idea that both, depending on circumstance, are true make this a case of not a thought out, logical rule of thumb to remember, but a series of case by case situations that need to be memorized. Never a good thing in a game as they will be forgotten at important moments, and/or you end up carrying around a binder that's bigger than the original rules with all the 'situations' that can come and running the checklists.
And I've gone cross-eyed...
To simplify stealth you could assume that all non-stealthed ships counted as having "stealth 1+" so that all modifiers were bonuses/penalties (rather than granting traits). Then scouting would work well, providing a -1 penalty to stealth (or, +1 bonus to the roll however you want to phrase it). For example an unstealthed ship hiding in asteroids (+2) before Scouting (-1) for overall Stealth of 2+.
This would leave, as far as I can see (please correct me if I'm wrong), two exceptions to the general pattern, Run Silent and the Leshath.
Run Silent would have to provide a different bonus for stealthed and non-stealthed ships, to represent the better savings turning off the lights provide for the beacon of an unstealthed ship's emissions compared to the already reduced profile stealthed ships possess.
Then the Leshath's unique ability, which then either goes:
1. up in power vs all ships (if scouting is applied last since it will negate all modifiers)
or
2. down in power vs non-stealthed ships and up vs stealthed vessels (if scouting is applied first, since it will reduce stealthed ships trait to +1 before modifiers).
I suppose the (fluff) question to determine how that goes is, does Scouting represent breaking the electronic countermeasures that hide the ships from sensors (scenario 2), or breaking the electronic countermeasures and compensating for the movements of dust and rocks and how they alter the firing solution (scenario 1)...
At the moment I agree with Ripple's statement, there's a lot of illogical contradictions in Stealth as I see it at the moment.