[pugs144]

Taken from another forum YMMV.

ACOG, Red dots, and optics in general don't "have" the Bindon Aiming Concept (BAC). The BAC is simply how the brain handles optical input and how it superimposes one eyes view over the other. ANY scope with a single, dominant focal-point/reticle will have BAC. Conversely, scopes without a dominant focal point (e.g. traditional German crosshair, mil-dot, and similar reticles) don't work with BAC because they don't have a dominant focal point. It doesn't matter if it's lit or unlit, it's all about having a defined, single point of aim (although lighting a good reticle design can make it more effective).

So, to answer your question, it's all about the reticle design. Since these scopes don't have reticles with a clear, single defined point of aim, they won't work with the BAC (or work very well).