If successful, not only is it ignored, the observer gets awarded Edge.
I don't get this part.
Please walk me through the reasoning why an observer would automatically get a point of Edge just for resisting a spell.
It's taking something of a liberty (aka, "Art of GMing") but it's trying to allow for the possibility of Edge gain during the sneak, rather than waiting for combat. Which is what your suggestion seems to be doing.
You asked me to explain quite a few things in that last post, I'll try to cover them all with one explanation. First, what is Edge and why do I think you need to be getting it during the sneak, as opposed to the sneak giving you edge during a backstab:
The concept is described on pg 44. It never explicitly says it's only generated during combat or whether you can potentially generate it outside of combat. During the intro, it uses a couple combat contextual examples, but it also uses language like "It’s both what you plan for and the unexpected moment when you seize an opportunity and make it your own" that to me says it doesn't have to be during combat. And indeed, we DO have explicit rule support for generating Edge during hacking (outside of cybercombat) and during social encounters. We also have Edge that triggers on the gear leg of the triad like Chameleon suits and certain augmentations. When you look at the rules for a Chameleon Suit, for example, it's implicitly obvious that you can earn edge while sneaking, even when that sneaking doesn't result in combat. I don't think there should be any disagreement thus far?
Assuming you CAN earn edge while sneaking as opposed to sneaking only giving an edge in surprise attacks in combat:
Look at the Chameleon Suit. It gives bonus edge for sneak tests. Ok, cut and dried, but rule zero is still assumed to apply. If you're already invisible, should you really still get the chameleon suit bonus? How could it affect anything if you're invisible? But still, if the invisibility is resisted and you're NOT invisible, then obviously you SHOULD get the bonus. None of this is illogical I trust.
Let's walk through a scenario: A ninja is trying to sneak through a dark warehouse patrolled by few sentries. The goal is to reach a crime boss in a well lit office inside the warehouse, and that area is much well guarded/patrolled than the warehouse at large. The ninja is wearing a chameleon suit and a friendly mage cast Improved Invisibility on him (and for pedantry's sake, we'll assume the spell covers the gear as well as the person)
If I understand your proposal Xenon, the process should work like this: The spell has a threshold (we'll say 4). The ninja should only roll 1 stealth check, without regard to the number of times they come into proximity with an observer who might notice them, and also without regard to the changing conditions across the entire infiltration (dark and easy cover and no bottlenecks, then bright and little cover and a guarded bottleneck that must be transited). Let's say that test results in 5 hits.
via whatever mechanic that resolves this, while crossing the warehouse and before reaching the guarded door, only 1 patrolling guard ends up being in position to potentially notice the ninja. You're saying he rolls a perception test once. If he gets 4, he sees through the invisibility. If he gets 5, he notices the ninja. In this particular iteration, seeing through the invisibility is irrelevant as it takes 5 to notice the ninja anyway. If the thresholds were reversed however, at 4 hits the guard would have heard or otherwise noticed the ninja, but it would take 5 hits to SEE the ninja. Repeat for when the ninja tries to get past the guarded office door.
So, if I don't understand your recommendation/suggestion, I apologize. what I just said is how I understand it, so as I attack it please accept a proactive mea culpa.
Problems with the above: 1) We have no idea if the ninja should have gotten edge for the Agility+Stealth test. If invisible, the effect doesn't even work. And we don't know if the invisibility works or not until after the guard rolls, which logically must occur after the start of the infiltration. So, literally: Ninja rolls Agility+Stealth. Does he get the Edge for wearing the suit while invisible, or not? You can't say, under this paradigm. 2) one stealth test for the entire infiltration doesn't differentiate between the very different contexts of one guard patrolling a vast, dark warehouse with lots of obscuring cover and one stationary guard just watching a well lit chokepoint. 3 (only potentially an issue) if your stealth test is better than the mage's spellcasting test, being invisible gives no mechanical benefit.
Walk through on what I propose/believe is the best "art" to adjudicate this scenario:
Ninja's mage friend rolls for the invisibility before the sneak even begins, as with yours. However the ninja does not roll Agility+Stealth at this time. We only have a threshhold for the spell. Then, once by whatever mechanic resolves that a guard came close enough to potentially notice the ninja, the observer will roll perception against the invisible status. If unsuccessful, we know the sneak suit will be irrelevant. If the observer IS successful, invisibility doesn't matter but the sneak suit will. Consider this a trigger point, for later explanation. Then, ONLY after this test, the ninja rolls Agility+Stealth. The suit either gives or doesn't give its gear bonus, based on what we now know about whether invisibility is in play. Additionally, invisibility either does or does not factor in for the circumstantial leg of the edge triad. Originally, I was saying the observer should now roll again to make this test opposed. However, I do see the merit in your argument at least for streamlining things, and can abide with the # of observers hits now being a threshold for the ninja to make a succest test against. One where we now know whether the suit or invisibilty is factoring in for edge for the ninja, as well.
Ok so, because I came around and agreed that 1 perception test instead of 2 (for one potential notice) makes sense, we do still have a bit of an edge problem. Delaying the Stealth test until after resolving whether the observer is affected by invisibility answers questions about whether the ninja gains edge on the Stealth test, it doesn't allow opportunity for the observer to gain edge during that same test. Ergo, the trigger point I referenced before. Giving the observer edge at that point (for successfully piercing invisibility) is just a way to give retroactive edge to the observer for the ninja's stealth test. Of course in this particular case, you might decline to give edge to the observer due to the sneak suit. Or maybe because it's dark and he doesn't have low light vision. or maybe you just award both edge and let it go as a wash. Adjudicating edge is an art, not a science. It's not legislated what gives edge and what doesn't, and that's by design. But the process needs a place to evaluate the factors for potential edge award. That's a hard need.
Of course, after the ninja gets past the warehouse patrol (either via stealth or combat) there's another "encounter" in getting by the bodyguard at the well lit office doorway. The process repeats, rather than one test representing an entire infiltration. This guard might fail or succeed to pierce invisibility without regard for how the first guard did. Also the ninja's Agility+Stealth roll is made in an entirely different environmental context (bright, little cover, a guarded chokepoint that must be passed through) than before, which can end up having completely different consequences for edge generation than the first test did.
Clearer than mud?
TL;DR
1) You get edge for stuff even outside combat, such as sneaking
2) You should manage the rolls for tests in such a way to allow for the potential TO gain edge for sneaking. for both sides.
3) combat isn't resolved in one test. Social encounters aren't resolved in one test. Edgo, an entire infiltration shouldn't be resolved with one Stealth test.