This is a feature that's unique to CustomFit. When there is a significant difference between hips and waist -- or between waist and bust -- a lot of decreases or increases need to happen over a short period of time. If you increase or decrease more often than every 4 rows, the fabric of your garment tends to bias in an unflattering manner.
Instead, we build in double or triple darts! Don't be intimidated by the terminology; they are actually very simple. It just means you will have 2 or 3 sets of shaping on your sweater front or back. You'll be working shaping rows at different points in your garment in order to get you the most flattering silhouette possible, while removing the threat of biasing fabric.
If you need help following your pattern's directions, please get in touch and we'll work with you one-on-one.