PlayCrackTheSky- Practically every type of yarn could and should be blocked. It evens out the fabric and the st's, if nothing more. Being a "natural fibre" means that it's not manmade (like acrylic, which is pretty much just different blends of plastic), so any type of animal fibre and plant fibre (like cotton or seaweed) would fall into that category.
The fabrics that benefit the most from a good blocking are animal fibres, because they are so stretchy. However, I've blocked swatches of shine sport before, and it really evens out the st's and makes any type of motif really *pop*!
The reason why I want to be able to block this yarn is so that I can make it easier for seaming and to be able to stretch it a little bit. For some reason, even though I'm sure I got the correct gauge, the width is off by about an inch. I was expecting this since I made a mistake and am off by 2 stitches, but not that much. Also, I'm off by half an inch at the collar too except the collar area too big. Thanks anyway for your answer. Any information is good.
On to the pictures.
The color is truer in the first picture. The second body part isn't pinned down quite as much as the first so it looks off from the first one. They have yet to be blocked. I just have the sleeves to do now. I'm banking on beginners luck with this sweater.