It's all waterfall or it's doomed to failure. You can call it anything you want, but you are still planning, gathering requirements, doing analysis, desgin, development, testing, deployment. You may do it one time or six, you may spend more time on one than another, but you're still doing it all.

Where IT people add value is the applying valid engineering princles to software and system engineering that allow us to replicate success.

Call it whatever you like.