Before we dig into what's happening and why, we should put this filtering problem into context by showing how it affects other textures that are less likely to show obvious seams between mip maps. Here's a pretty good example of how much this problem affects most textures in the game.
You can see some minor aliasing in one of the texture seams at the top of our sample images, but that's about it. There are more mathematical differences between the images that show up in the full "diff" image, but they're not massive. Whatever's going on here doesn't harm image quality too greatly, but it does cause problems in certain cases.
|OCZ RD400 NVMe SSD heats up the enthusiast storage game||27|
|Samsung's 750 EVO SSD family grows with a 500GB model||8|
|Report: Windows Phone market share drops below 1%||69|
|Cryorig teases a distinctive pair of Mini-ITX cases||32|
|Radeon Software Crimson Edition 16.5.3 gears up for Overwatch||13|
|Rumor: a GP102 GeForce Titan and GTX 1080 Ti are in the works||116|
|We need your input as we plan the "second-10th" TR BBQ||30|
|Revive patch developers fire back by disabling Oculus DRM||32|
|Nvidia 368.22 drivers are tuned for Overwatch||18|