In the beginning there were two images. Concentration allows you to see one. The muscle memory comes from performing the task without thinking or forcing. Like eating, you don't poke your mouth with the fork tines, because you have performed the act with out thinking. (Here subconcious.) When you hold for bullseye shooting you probably don't think about pulling the trigger. It probably happens (subconsiously) on demand. I don't know a whole lot about bullseye shooting but the patience for it must be far more focused than I could muster. Hope I can help and I appreciate the effort.