Mike in TN
Participant
Post count: 292

The previous posters are right on with their answers. This is standard practice with most woodworking to eliminate waste caused by warping, bowing, and cupping.  Very short and very long pieces are normally more difficult to manage at the bench and there are circumstances, such as running molding, where it is easier to keep pieces longer to facilitate the work but it sound like it would definitely  be to your advantage to rough cut the pieces first.