The original article describes the careful technical tradeoffs and mixing/matching of techniques that is required to pull off a game like Bioshock Infinite on ancient hardware (at least as relative to current PCs and high-end GPUs).
Interestingly when Unreal Engine 3 was first being demonstrated to potential licensees and in the media, it was using a very high quality and elegant one-pass per light rendering algorithm. The demo scenes were basically a room or hallway with several colored lights, and the resulting multicolored shadows cast by an animated character. In 2004/5 this blew people away and a lot of game executives signed expensive licensing deals with Epic. No games to my knowledge actually shipped with that type of lighting, at least on a console. Then Epic and engineers like the author of the article spend the next several years (an entire console generation really) retrofitting UE3 with actually practical rendering technology that involved a lot of sacrifices, careful balancing, and artist headaches.
This generation Epic is showing a mind blowing UE4 demo with Voxel Cone Tracing and the cycle starts again.
One thing is very clear to me, Irrational threw out a ton of invaluable institutional knowledge when they laid off that team. I suspect competing studios, especially those using Unreal, are scrambling and having a bidding war trying to hire them.