Solved!
Thank you everyone for supporting me.
I felt well enough to have a fiddle around today.
@salmonmac I tried several times but I kept having legs sticking out from the back of the icord so I’m not sure how working it on the WS would help me as it would put those loose legs on the RS ofnthe top. It obviously works for the person doing the tutorial and for you if you use it. I even tried pulling hard on thenyarn to tighten up, i never pull like that on yarn but itmseemed the onky way to get a half decent result. I noticed the RS of the icord was much neater so tried working from the RS which I almost accepted but the stitches were bigger and not as neat as I’d remembered on my original neck so I continued fiddling.
@FluffyYarn oddly enough I found the exact tutorial you posted in my saved bookmarks, so it must have meant something at some point - perhaps I’d planned to use it but then chose to bind off and not have the live stitches needed for that method .
I was convinced nimble needles had a tutorial which had meant something to me and reviewed them all in hopes but no.
Then I watched a zillion icord tutorials from all sorts of people and none of them was the right thing.
Then I came across this
Which is still not how I did it but it rang a bell with me and I realised this is a rare tutorial where stitches are picked up and knitted before starting the icord. Not live stitches, not picking up one stitch at a time.
I was even more sure I’d picked up all around before beginning the icord. The benefit of these stitches all picked up is they can never enlarge the way one new stitch at a time can because the single stitch is attached to the working yarn but the full round is limited in size by being wrapped around the needle.
Unfortunately she doesn’t show exactly where she picks up those stitches. And the icord is worked differently too.
Eventually I worked out what I’d done wrong was picked up in the centre of each stitch instead of under the cast off bars at the top. Picking up in there and working a 4 stitch bind off instead of 3 stitch to make it the right width. And I’d cracked it!
I’ve watched soooo many tutorials and none of them use this method so where did it come from?
I can only assume my brain mashed a few different things together and came out with a nice result. The inside looks almost as nice as the outside. I didn’t have to yank on any yarn but they are nice and neatly formed and consistent, no legs poking out, no weird loose bits or big stitches, and no cast on edge peeping above my icord edge.
I haven’t grafted the join of the beginning and end yet but when I have, and when I can manage a pic, I’ll post one.
Thanks again everyone!