Thread: Scope levels - do they work?

I remember a long thread about scope levels on the other forum.
Todd Hodnett also describes and stresses them as CRITCAL for longrange shooting in the Magpul Art of the Precision Rifle (or similar title) DVD.

I don't like them and can't see how such a level can work unless you have it in your field of view simultanously as you have your sight picture.
Here is a short film I made on the subject