Just because a computer can generate random numbers more accurately than a human (which it can), doesn't mean it has an edge in unpredictability. In a given round of a Single Battle, you have, at most, 9 choices (4 moves and 5 Pokemon to switch to). Exceptions include Baton Pass and U-Turn, where you pick a move and a new Pokemon. It doesn't take much to see that most of your choices in a given turn are bad ones. Hence, a truly unweighted random algorithm for move selection is a bad idea.
On the other hand, we were discussing how to find the best probabilities for the best randomness in the other thread. Which is more or less, how an AI would work.
One trivial game which has been solved for example is Rock-Paper-Scissors. It has been mathematically solved to show that 33.33~% of the time you should use Rock, 33.33% of the time paper, etc. etc. Now this is a simple and easy case. Nonetheless, with weighted rock-paper-scissors, it can also be solved.
And this applies to Pokemon because it is more or less a generalized rock-paper-scissors game. Instead of just 3 choices, you have upto 9 (4 attacks, 5 pokemon to switch to).
Now, I know you weren't arguing that it was a good idea, but here's where I'm going: most of the time, you have 2 (maybe 3 or 4) valid options. For instance, if your opponent switches, Choice A is better. If your opponent stays in, Choice B is better. Maybe you need to decide between Pursuit and Sucker Punch or some such. If you want to introduce a factor of randomness so that your opponents can't predict you, it doesn't take long to flip a coin. At worst, you have to roll a die.
Now Nash proved that in any game, there is a Nash Equilibrium. It can be a mixed strategy equilibrium however. And with that said, the weights can be arbitrary.
One method to doing the AI is to somehow solve for this Nash Equilibrium, the best probabilities of randomness assuming your opponent is also perfect. Of course, by the definition of Nash Equilibrium, it would be your optimal strategy even if the opponent changes his strategy.
Although I haven't yet, I'm seriously considering including a coin flip when decisions like this come up. I'd be interested in hearing opinions on this strategy.
Again, I'd say you shouldn't do that. The "best" probability is arbitrary. For all we know, the best case is choosing sucker punch 80% of the time, and choosing pursuit 20% of the time.
This may seem a bit like magic to you, but...
1. Nash did prove that one of these points exist. That there is a strategy that you gain nothing from deviating from it.
2. It -might- be possible to calculate these points.
So with that said, if a computer can calculate these points, and then make a perfectly random choice every time, with the perfect weights assigned to each decision, then we'd have an AI that would be very difficult to predict and very difficult to beat.
Course, we didn't reach that point in the discussion yet. So... yeah. I hope it is possible :-p