Triangles are not evil, but my brain sure can be on some days. Be careful not to stretch the bias direction. I don't have any trouble sewing them, but sometimes I cut them too small. I'm on my way to JoAnn today to buy more fabric because I cut the setting triangles too small for the on-point Christmas quilt I'm working on. I Hate when my brain does evil things like that! BTW, this quilt has 4 bias sides on every square. It might as well be triangles!