(I haven't checked the link you gave as my internet data allotment is almost used up.)
But, when I do redwork I use a very thin fusible interfacing on the back of the block BEFORE I do the redwork. It helps to hide anything you wish not to show. The weight of the fusible is thin enough that it makes the blocks just a bit 'sturdier'.
When cutting the setting triangles for an on point quilt, I cut squares in such a way that I am certain the outside edges of the quilt are on the straight grain of the fabric. AND I cut those squares larger than they need to be so that I can float the blocks and not lose my points in the seams of the borders. I have a tute in pdf. format that I will be happy to share with you if you will PM me with your regular email addy.
Jan in VA