There are three different methods of pattern alteration one may use - the original slash and spread, the pivot and slide which was more accurate in many cases, and now the "new" seam method which was developed off the pivot and slide but is much more "user friendly". It has produced many "Ah-ha" moments for those who alter existing patterns for better fit. A British sewer declared that it has "revolutionized her sewing!” It is by far the easiest and most accurate way to alter a pattern. Another new development is the order one should follow in checking your measurements and doing the alterations. This has made a world of differences in understanding where and when changes need to occur on the pattern.