Wow, you might want to have your facts straight, since you are WAY off. "Running up the score" and "comfortable lead"? That injury happened in the first quarter, with no contact, when the Texans where up 7-0, on the Patriot's first drive, and on Welker's first catch.
The fact that those guys were playing is something that can be argued, but Belicheck almost always plays his guys, the chances of an injury are relatively small, they did just play 15 other games without a serious one.
That team just wasn't that good, BB wasn't happy with it, and was still trying to get the team to improve on the way to the playoffs. They ended up losing that game by the way.
SSDD