I glue baste, and if I know I'm going to be densely quilting the quilt, I won't even bother attaching the batting scraps together! I just glue them down to the backing a strip at a time, making sure edges meet neatly and trimming anything that overlaps. You can't tell at all in the finished quilt. I wouldn't do it for a quilt I'm doing minimal quilting on, but on something that's going to get an all-over FMQ design that's pretty dense it totally works.