First, sincere apologies to Charlie and Bucs Dugout for having too much copyrighted material in my original FanPost on this.
In today's PG article on Steve Pearce there are quotes from Don Long and Pearce on the subject of having a plan at the plate.
Long talks about pitch recognition, Pearce talks about launch position and ... well, nonsense.
It sounds like Pearce's "plan" is to get in the box hoping to "feel" right. Presumably, he would then see a baseball (not fastball or breaking ball, etc.) and swing. Things like location, trajectory, and speed don't seem important if Pearce's hands are a "certain way." And just what way is that anyway? I doubt Pearce even knows.
Internal analysis is essential and useful, but it's for practice. Where and how you stand and swing when you're in the box in a game should be rote mechanics. They shouldn't be in your mind at all.
External analysis is also essential and useful -- for the game. It's an analysis that should start before you're in the on-deck circle. When you step in, you should be thinking externally.