Variety is what the 3-4 can give you. You can play the 3-4 without having superstars, so to speak, in the defensive line.
At the time we didn't put another linebacker in. We took one of the defensive linemen off the line, stood him up and went into the three-man front that way. We did it in obvious passing situations, long-yardage situations or at the end of the game when we were protecting a lead.