Plan:
1. Copy existing jacket pattern to tissue paper. Will use tracing paper...
2. Build a jacket using some scrap stretchy fabric of some sort (not the fancy stuff, not exact stretch, but hopefully close), minus zipper!
3. Check fit.
4. Adjust fit, deconstruct adjusted jacket.
5. Transfer adjusted jacket to pattern
6. Build jacket with new fancy softshell.
Getting the collar length is going to be a bit of a challenge.
And I think the bottom of the jacket probably should be a straight line... I think I flipped the wedge part. I will have to watch that.... I guess I can cut the jacket slightly long and adjust the bottom, however, as it needs to fold back over on itself.
Someone's video on shortening a separating zipper.

@ai6yr open-lower-back wedge cut, tied with strings.
Go kink/medieval on that bitch.
@ai6yr DOOOOOO EEEEEEEEEEET. You WANT IT.
Search your feelings. You know it to be true.
@ai6yr ::stares::
WELL..... ???
@ai6yr BTW one of the weirdest but comfiest pieces of clothing I own is an odd combo/mix of rain shell and a short cloak. It has wide sleeves, a hood, and closes by buttons front of shoulder/collar bone, one of those turned inside (told you, weird)
It looks like something out of a new Star Wars movie set. I'd wear it more often, but I don't want to look TOO MUCH like a scifi movie extra, walking around.
@ai6yr make the collar a reversible hood.
The fastening in front must be loop n peg. Bonus for the teeth or claws of whatever tried to kill you last.
Hoodie ... I made a hood for a knitted sweater and ended up with pointy hood, and regretted it. Fortunately it is red, not white, but still I wear it with the pointy part tucked in.
Next time, I would make it as a rectangular strip up the back of the neck and over top of head, and two other pieces, one on each side of head. More seaming, but fits and looks a lot better.
@EugestShirley yes
I understand that, thank you so much for assuming I am an idiot.
Me, my History degree AND my couple of years actually wearing things that are shrapnel and bullet proof, made with padded kevlar among others thank you immensely.
I suggested, jovially and in jocularity, that it'd be shrapnel proof, were it made of padded kevlar.
::eyes roll interdimensionally::
@EugestShirley P.S.: I am my very own source, actually having been shot at and blown up.
Toodles.
Yeah, it was a very odd response. Internet ppls can be weird.
@ai6yr @mattblaze @CliffsEsport @EugestShirley @faraiwe
I sympathise; I was trained to regard the word plane as describing a flat surface, or a tool for making such. But also, I tried reading Beowulf once and it was ruddy impossible. At some point I think we have to concede the fluidity of language. The annoying thing is that it is allllmost static in the human lifespan.
@CliffsEsport @ai6yr @mattblaze @EugestShirley @faraiwe
Wow, interesting background. Yes. The more common error is saying "memory" and leaving the listener to guess from the context and amount described. The tricky thing, I find, is that as the rate of globalisation increases, and where English functions as a lingual franca, it is hard to begrudge those who don't speak English as a first language using words improperly. At that level I think "properly" is just whatever has an acceptable likelihood of arranging the neural pathways in my skull in the intended manner. No excuse for the rest of us, of course.
@mattblaze @CliffsEsport @ai6yr @EugestShirley @faraiwe I feel obligated to resuggest my suggestion

If this works.When I mentioned a WIDE hood that would fall down to shoulders, covering shoulder-wide, I meant this.
Since I do NOT sew, I have NO IDEA about the nomenclature.
But it's hella cool.
@ai6yr there’s this comment I read “zippers do not support pulling out tension, are not designed for that” I’ve damaged zippers in bags I made because of that: using the zipper to contain.
Yo may want to add a couple of long strips, about 1.75” to 2” wide, to anchor the zipper to the jacket.