You said this:
This calculation relies on the implicit assumption that the value provided by the core game is exactly the same now as it was a year ago, and that's only true if the game provides no value over time.
I didn't feel the need to respond, because I already stated it when responding to panda and alan, not mentioning that you were rude. If that were the case I would be comparing it to the price of the base game a year ago, or at release, which is I believe 49.99 or 59.99. At the least, I would have added the current 14.99, which I did not. As I stated, I'm satisfied on the amount I paid at the time, and have no gripe about people paying less--I understand the concept of time discounts or net present value. I was comparing current prices for all bundles, and was noting that there is only a price difference of 2 cents. Of course people with less willingness to pay would buy only when the price is lowered.
Maybe they don't teach price discrimination in Econ 101. I'd recommend you take a game theory or IO class. I don't think I want to go into detail, but my point had to do with the specific price discrimination strategy, and if you want to understand, please read what MaxQuartiroli wrote. His point is fair, though I can't say that it is a good long term strategy in EA's part.
Again, even without time discount, I understand the reason for digital game prices decreasing with time as an indirect price discrimination strategy. People with the highest willingness to pay would have already bought the good, so with time lowering the price makes additional revenue, and as a digital good, there is close to no marginal cost involved. Just a matter of figuring out what the sufficient time to lower certain amounts would be. Again, no problem with that.
And yeah, I think I'm just going to go with Trespasser.