I've totally botched the Ice Queen cowl I was making. I've frogged it, and I'm going to start it again. I'm inexplicably dropping stitches and not discovering it until 40+ rows later. The stitches weren't unraveling (thanks to my lifelines), but they were too far away--and there are yarnovers and knit-togethers--and it was just not possible to recover.
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(This photo is about 20 rows in. I had 60+ rows when I ripped back.)
But I am not going to be defeated by simple yarnovers and knit-togethers. It's a simple feather-and-fan pattern(!), and I've done that before. I think the problem is just super-thin yarn on very slippery needles. Since the yarn sticks to itself a bit (it's alpaca), dropped stitches don't show up as such. I only noticed several unattached loops as I was looking back at the beginning section. I'm just going to have to be obsessive about counting stitches (there are 26 to 18 stitches in each pattern repeat); and if there's a stitch missing I've got to stop assuming that I skipped a yarnover and start looking for something that has been dropped.