This appeals to me as it eliminates the process of taking the block off the paper when you have finished stitching and then having to fish out all those tiny bits of paper that have got stuck behind the stitching. What a pain!
Using the freezer paper you crease the paper along your drawn lines and then fold it out of the way leaving you free to sew next to the fold but not actually through the paper. When you have finished the block it is simply and easily peeled off the freezer paper.
However you can see from the photo that you still get a very accurately pieced block.
This block is taken from Carol Doak's book 50 Paper Pieced Stars