To me a good shed is a complete shed. Some snakes especially larger ones it will tear and often you get multiple bits. Bad sheds are stuck and often in many bits. I often get off my big girl (3700gm) a large piece of the lower labial scales down into the keeled ventral scales. The upper labial scales and often ending keeled dorsal. The rest is often one large chunk or two. She is very large and a complete on piece is rare. The smaller snakes on chunk is common although sometimes the lower labials and shield scales tear away.