A unique style of blocking offensive lines is called a cut or slice. Over the years, some have called a cut or minced block a “dirty” technique. A cut works very well and if taught correctly can keep a dominant defender at bay. Slashing or cutting should never be attempted with the ruthless intent to injure any player. I would get confirmation from the association’s rules that slashing and slicing is allowed before teaching it to any player.
Offensive linemen, and sometimes other blockers, use a slice blocking technique, legally blocking below the waist (i.e., from in front of the defensive player) in an attempt to drive defenders to the ground, rendering them unable to chase down a running back for the short time it takes for the back to find space on defense. The technique is somewhat controversial, as it carries the risk of serious injury to the legs of blocked defenders.
The San Francisco 49ers of the 1980s and early 1990s were famous for their slicing technique (and leg-whipping blocking techniques, which is not legal), a maneuver that was finally used in the mid-1990s by the NFL’s Denver Broncos. The Denver Broncos gained a level of fame using their cut-blocking style (often called a slick play by other teams) that produced the best rushing offense in the NFL for over ten years, but also caused many the Broncos’ defensive football opponents to be injured from cut blocks. In a Monday Night Football game in 2004, Cincinnati Bengals defensive tackle Tony Williams was injured during the year after a cut block (by Broncos lineman George Foster), and in 2005, Jacksonville Jaguars defensive guard Paul Spicer was seriously injured on a cut block by Broncos lineman Matt Lepsis. In response to the complaints, in 2004, Broncos head coach Mike Shanahan explained to local reporters and showed them a film of an NFL game (only seen and used by coaches) demonstrating how nearly every NFL team uses the cut-block technique.
As you can see from the paragraph above, there is a lot of controversy in the NFL regarding cut blocking, so be sure to exercise caution if you decide to teach cut blocking to your youth football team. It is important to only show safe and legal techniques for potentially dangerous blocking. We use a simple but safe rule regarding cutting blocks. Only if you are being beaten and you can stay on all fours can you block. Our coaches make all the players drive or get on all fours against the defender.