1) The feathers seem to me almost obviously to be Sabrina's... In fact it occurs to me that Sabrina as a witch would be pretty much the ultimate in scary monsters, and many of the limits which she runs into are because she doesn't have access to the fugue mentality which drives a witch's power. As a witch... she'd effectively be able to shut down pretty much anything Witch or magical girl related... and might even be able to cannibalize other witches for greater and wider scope of power.
We have discussed this quite a bit (of course), and the reasons that we told Homura and Mami that we don't think that we are the cause of the Feather are the same reasons that mean that Dedolere is probably not the cause of "Feathers":
1. The Feather didn't feel witchy.
2. The Feather didn't show up the first time we made a Barrier.
In addition, there are a couple of other reasons not to suspect Dedolere:
1. We can sense Dedolere within our soul gem, and it is quiescent.
2. Oriko said that it's not a witch and that (given the right tools), Sabrina can "end" the threat. I'm not sure exactly what that means (it's one of the things that I'd like to talk to her about to get clarification), but it doesn't sound like she was talking about our witch.
3. Firnagzen has said that if we ever do witch out, then that will be a Bad End of the Quest.
2) It seems to me also obvious that trying to 'heal' the Grief-seeds is the wrong approach because really you don't 'Heal' the soul gems, you heal the bodies which they're connected to... Instead I can't help but think maybe with the clear seeds what you should be trying to do is make bodies made of grief and/or magic for them, then connect them (the ones in the clear state) to the bodies.
I agree that we're not likely to make progress with dewitching until we have a body. But I would prefer to have an actual flesh-and-blood body to use rather than a grief/magic simulacrum. Current possibilities for creating a body include: repurposing a corpse, cutting off a finger and growing a full body from it using healing (magical girl mitosis), and creating a body completely from scratch (using a grief scanner and 3D printer).
3) The scene in Sabrina's barrier makes me think of Sayaka's transformation scene into Octavia. Essentially the gem takes over, the body hangs limp and the new 'self' which is the main body and the barrier encompasses the gem which then discards the old body and the old identity. Familiars and everywhere inside of the barrier are part of the 'mind' of the witch, the main body just being a functional focus point around which its 'thoughts' and 'dreams' enfold. Create your perfect world...
Sabrina creating a Barrier and populating a Labyrinth has a lot of similarities to a witch doing the same. But there are also some important differences. Our gem doesn't explode and we don't abandon our body. We don't create Familiars. The resulting Labyrinth is not inimical to life and has a more realistic style than any of the Labyrinths that we've seen (except for Homura's, and she wasn't exactly a witch at the time). We also have complete control over our Barrier and Labyrinth, which is an ability that has not been demonstrated by any witch that we've seen thus far.
4) Has it ever been thought of or proposed that we should try to make familiars of our own?
The idea is brought up occasionally. Given that we can make a Barrier, it should be possible to make Familiars as well. But that doesn't mean that it would be
wise to do so. Most witch familiars are antithetical to human life, and even if our familiars are different, there's still the whole ethical question of whether we ought to create new life.
Now one of the most interesting things is basically the existence of the 'Grief Spiral' which is basically the defining factor point at which a Magical girl crosses over into witch-dom, that self-obsessed moment of absolute despair unable to see anything but their own misfortunes until they retreat into their 'happy place'. Reaching out to the Grief-Seed seems to me to be like reaching out directly to a Soul gem separated from it's body. Ie the person is there... but they're insensate, because they literally have no senses, not body with which their Soul can express itself.
Note that "Grief Spiral" has generally been used (in this thread) to talk about the point in time where a magical girl gets depressed and starts the exponential buildup of grief in the soul gem, like Sayaka did in canon in the days leading up to her demise. We use the phrase "witchout" for the actual transformation into a witch.
Also I'm kinda curious as to what the effect of creating a witch's barrier within a witch's barrier would be like.
I also am curious, but that experiment would probably be risky and I would say that (if we ever get around to experimenting with Barriers again), we should first try to setup a Barrier
next to the witch's barrier before trying to setup one from inside. This would test Mami's "lightning rod" theory.
Maybe we should try to investigate the connection between Sabrina's own body and soul-gem or try something similar so that she has a better understanding of the connection between these two things.
Agreed. One experiment that we have been meaning to try is to see if the 100m grief control range extends from the gem or the body (or both). If you can think of any other experiments we can do in order to better understand that connection, then please feel free to suggest them.
One thing I'm fairly sure of though, a Witch won't just 'revert' to a magical girl... even if fixed... I'm pretty sure we'd be looking at a completely new type of entity either way.
It might be a bit different than a magical girl (we have removed a
lot of grief from a clear seed which presumably would have been present in the soul gem, for one thing), but it would still be a soul within a rock connected to a body, and it would (presumably) still have magical powers, so the resulting entity would still be more similar to a magical girl than it would be to anything else that we know about. But in any case: as long as the person retains their memory and sanity, then I'll be happy.