computer calculations can never truly factor in the whimsical nature of freedom of choice.
I think you will discover that many people here believe that if anyone or anything can "factor in the whimsical nature of freedom of choice", then computer calculations can do it too.
The dispute is mostly about whether or not to assume that the other players are rational. In the absence of good empirical evidence about the other players, I think you have to assume they are rational. My rationale? Well, if you don't assume they are rational, exactly what do you assume?
Perhaps the best way to justify the assumption of rationality, though, is to imagine that you are the acknowledged guru on this particular game. And you are offering advice on your blog (which everybody who plays the game reads) regarding choice of sword and armor. So what advice do you give? You had better advise your fans to choose their swords and armor using the mixed strategy Nash equilibrium. Because if you advise anything else, all your fans are going to be pwned.
"Ok", you say. "If I imagine that, then I see what is good about Nash equilibria. But, why are you asking me to imagine stuff?"
Unfortunately, I don't have a good answer to that question.
Note: this image does not belong to me; I found it on 4chan. It presents an interesting exercise, though, so I'm posting it here for the enjoyment of the Less Wrong community.
For the sake of this thought experiment, assume that all characters have the same amount of HP, which is sufficiently large that random effects can be treated as being equal to their expected values. There are no NPC monsters, critical hits, or other mechanics; gameplay consists of two PCs getting into a duel, and fighting until one or the other loses. The winner is fully healed afterwards.
Which sword and armor combination do you choose, and why?