I once made a scarf with the technique my mom taught me, but i don't know what i did different, maybe it was the yarn i used, but it ended up feeling bulkier and heavier than the first one i made (that i lost, i should look for it).
That doll looks more like Amirugami, which uses crocheting rather than knitting techniques. But I think he does both (since he had knitting needles in an earlier episode) so it's no big deal. XD