Originally Posted by feline fanatic

Before you decide to omit the flange (referred to in the pattern as basting strips) can you tell us if the outside edges of the quilt are on the bias? This may be why the pattern wants them and refers to them as basting strips as opposed to a flange. When a pattern ends up with the outside edges on a bias you run great risk of stretching it out of shape in the process of finishing it, simple handling can stretch a bias edge out of shape and quilting can definitely do it. If you want to omit them, that is fine but then you should put a basting stitch around the entire outside edge of the quilt top. If you can at least post a link to the pattern you purchased, we may be able to tell by looking. Bias edges would be very common in quilts made out of nothing but triangles or quilts set on point where the pattern author had you cut the setting triangles from squares cut in half diagonally (as opposed to squares cut in quarters where the outside edge would be on the straight of grain). Many pieced borders can also end up with bias on the outside edge, like a pieced chevron border or spiky paper pieced sawtooth edge as is common in some of Judy Niemeyer's patterns.