As all good and proper individuals do, I was wasting some time reading random entries in TV Tropes. In case you haven't started, TV Tropes is a web site where they take all of the old, tired tropes from pop culture and index them. It's a fascinating read, and one of those things where you don't realize that you've been reading the alarmingly numerous amount of examples of how the two-way radio getting disconnected is vital to moving the plot along.
Anyway, I was reading the entry on the Indy Ploy. The Indy Ploy is where a character has no idea what they are doing...which is perfect, because then there's no way for the enemy to counter it. Basically, because Indiana Jones (or MacGuyver, or Captain Kirk, or whoever) is making it up as they go along, their enemy at the moment has no way to predict what they are about to do...or if they think they know what he is going to do, it will turn out wrong.
Of course, TV Tropes doesn't just apply to TV. Most entries have a "Real Life" example, and the Indy Ploy has plenty. For example, it can be used in chess, especially against computer opponents; while you do want to use strategy for most of the game, because of an AI's brute-force method of playing it has the ability to counter it fairly easily. By throwing in some random moves, it makes it difficult for the AI to predict exactly what your overall plan is. Of course, you need to be able to back it up. Doctor Who is also a big contributor to this trope, especially during the reboot where The Doctor spends most of his time making stuff up as he goes along.
More importantly (to me, anyway) is the introduction of game theory: in that dismal corner of the science, an inferior "plan" can always be countered by a better one if the plan parts are all well known. The only way to counter it is to take some random moves, effectively "ruining" the best-laid plans of your rival.
And for those who don't know, this trope is more or less how modern football was created: the forward pass was an unplanned decision to get out of a situation, and its appearance was noted by Johnny Heisman.
Implicit in all this is that you can't simply act randomly and let it play out; you have to have the ability to improvise and use good judgement. "Random" probably isn't the right word; "unpredictable" is probably closer. Basically, making the "right" decisions without planning ahead will always confound the person you are trying to outwit, because they are assuming that you have a plan. Of course, if you want to bump this trope up to iocane powder-levels of meta, if your rival knows you are not planning anything, that in and of itself is a plan...
Anyway, the entire point of this post is that here is something that includes Indiana Jones, game theory, Doctor Who, and football. It's like someone is reading my mind.