I’m getting back into knitting after many years (not that I was ever an expert, but I had successfully completed a few sweaters), and my first project is a pretty simple sweater made with chunky yarn. Here’s my question: Due to a kerosene heater episode, the first sleeve I finished got some soot stains (in spite of being in a plastic bag for protection - guess it wasn’t closed all the way). So I called the yarn store for advice, washed it in Dawn, and in the process it stretched some (I guess this is normal? 25% wool/75% acrylic). So then after finishing the second sleeve I washed it as well, in order that when I assemble the whole sweater they would be the same. (1) Am I now committed to washing the front & back as well, before assembling the whole sweater? (2) Is the norm to wash all pieces before assembling, or after? (3) I saw a comment on one of the forums that with synthetic yarn, blocking is not necessary. Any thoughts?
Thanks in advance for the help!