I am a regular ed teacher who has many special ed students mainstreamed into his class. I have to work with spec ed teachers quite a bit, so I'm just going to proffer some impressions.
1. My spec ed colleagues work with an incredible amount of bureaucracy. They keep huge folders full of useless data, have to have meetings to decide minutiae, and are generally hampered by legal matters.
2. My spec ed colleagues work with students that are especially difficult. Disabilities come in a wide range, and are present in different students to varying degrees.
My opinion- I'm not able to do what my spec ed colleagues do.