If you play with subtitles at Kat's death, once it goes all black you can see subtitles, but you cannot hear anything but the music. The subtitles say something along the lines of : "Close the doors!" "It's going to be okay." But there is much more. Is this just to emphasize the damage the Covenant is dealing? Because it sure saddened me to see those subtitles. They seem like civilians, but I don't know why they would be in one of those buildings.
So the point of this, is that maybe there is something hidden in these subtitles. Or it's just to emphasize the sadness of Reach. If it's the latter, it truly worked. I definitely felt sad when I saw those words.
If you think it's the latter, describe how it makes you feel. If you haven't seen this, go play New Alexandria with subtitles on!