What is that idiot talking about?
Cut blocks. The Broncos are famous for using cut blocks where the o-line aims low on his block, cut blocks are the most likely legal blocks to injure a d-lineman, so when d-lineman see an o-lineman aiming low their first instinct is to protect their knees and ankles.
Broncos have a reputation for blocking low, particularly on running plays. There was a little rift between Cowher and Shanahan over it last year, so the Broncos offensive blocking scheme will be one of the "storylines" the announcers try to develop this week.