A cop suffering from multiple personality disorder discovers a plan to detonate a dirty bomb in 2 hours, what he doesn’t know is: the perpetrator is his alternate persona.

Don't worry.

These are just very useful tools to improve and develop your idea... and don't fail. Just as Logline.it.

This is what I wanted to tell when I wrote:

"This is why final loglines are almost always different from initial. If not, this can means two things:
1. You where lucky,
2. You lost a lot of chances to improve your story."

>>Contrary to Blake Snyder , I think there is no bad ideas in cinema or litterary...

An alternate POV: "Test Your Story Concept"

Tony Edward's logline is better because it makes your hero more dynamic; and your story better outlined, with more mistery and suspense.

This can be helpful to develop your story.

According to your own premise, you can say "all the clues to a complot by an elusive terrorist".

DID are related to a childhood trauma. Your hero will have to find why his alternative part wants to make a dirty bomb detonate.