So now you think it's a good idea that both vendors should start financing the game developers and write custom codes (which in this case would be the same since the implementation is standard) which locks the other vendor's card out from using a common feature like AA? Did ATI lock NVIDIA's cards out when they helped developers with the DX11 games when NVIDIA didn't even have a card out?
Before Nvidia came up with this code. No games using this engine could do MSAA under directx 9, so it's a common feature in general, but not in this situaiton. So if the option is one group of users can use MSAA or no users can use MSAA, I choose option 1 all the time. Especially since the other group of users could have also used MSAA if their vendor had bothered to come up with their own code instead of just bitching about vendor lock.
Unlike this code that enabled MSAA for this engine under directx9, directx 11 is a standard, not a work around. If the game is marketed as a directx 11 game (and not a directx 11 game if you have an ATI card), it better run under Nvidia too. If it is marketed at directx 11 only if you have ATI, then it sucks to be a Nvidia user if you want to play this game under directx11 but at least you go in knowing what's up. I'm pretty sure Batman was advertised as having AA only if you had an Nvidia card.
Also, in regards to ATI helping with directx11 games when Nvidia didn't have directx11 cards out... what better form of lock is there? You get the buzz/good press of helping a developer implement advanced features, at the same time highlighting the fact that your competitor doesn't have those features. It's actually genius.
This code ended up running equally well under ATI and Nvidia cards, but what if it didn't? Nvidia wasn't going to test this code against a wide range of ATI cards, what if it didn't run well or caused problems for some ATI cards? Then ATI fanboys would be complaining about Nvidia writing code harmful to ATI cards and playing dirty by having it incorporated to a game?
Let's face it, for a lot of the newer games, they're just ports from consoles. The developer will not spend the resources to add enhancements for PC versions that weren't there for the console. Heck, Star Craft 2, the biggest PC only game in years didn't have in game AA. If Nvidia or ATI don't write custom code for certain features, those features just won't be there. Whether you or I think custom code is a good idea or not, it's a reality if you want features above what's available on the console version.