The N.F.L. says it is not surprised by the spike because it was a point of emphasis when officials convened before the season for their annual clinic, where they are shown in video form how the league wants the game officiated.  “We’re not going to let up in trying to protect the players,” Mike Pereira, the N.F.L.’s vice president for officiating, said. “The clear message is being sent — we’re going to protect the head and we’re going to protect the knees and we’re going to do that on those most vulnerable.”  Pereira often hears complaints that big penalties should not be called late in games, lest they affect the results the way Lewis’s hit on Ochocinco helped the Bengals on their winning drive last week. That, Pereira said, is not realistic or fair.  “That’s like telling a team, ‘We’re in the last minute, so take advantage,’ ” he said. “Not going to happen.”  And although the low hit on Brady by Baltimore’s Terrell Suggs might have been a questionable violation of the rule that is interpreted as prohibiting hitting low in the leg with force — the so-called Tom Brady rule, after Brady’s knee injury last year — Pereira said it was appropriate for big-picture reasons.  “The last thing I want to do is lay off those calls, because then you’re sending a message that it is O.K. to go low on the quarterback,” Pereira said. “That’s not a message we want sent.”  The message may need some honing. The Ravens were enraged by the penalty on Suggs, who after the game summed up what many defenders were thinking. “Maybe next year, it’ll be two-hand touch to get a sack,” he said.  The Giants owner John Mara, a member of the competition committee, said: “I have seen some calls this year that I haven’t been pleased with. But as painful as it is if you’re that club, in terms of the effect on player health, if it keeps a quarterback from getting hurt or a defenseless receiver from getting hurt, I think it’s worth the trouble.”  Tony Dungy, a former coach and current NBC analyst, says he agrees with the intent of the rules, if not the execution in enforcing them. Dungy said defenders were flummoxed because the rules’ language was ambiguous and the calls were inconsistent from game to game.  “You know as a defensive player if I hit in the head, it’s a penalty,” Dungy said. “But then when you say you can’t go low with force, what is forcible? Terrell Suggs was not forcible contact. You’re better off saying you can’t contact below the thigh. Defenders are saying, ‘I’m trying to get a sack and I didn’t think I used great force,’ but how do you know? What frustrates defensive players is ambiguity. It’s like hitters in baseball; you just want to know where the strike zone is.”  The greater problem, Dilfer said, is that defensive players — he was one until he was switched to quarterback — are taught to bury their helmet in their target and then explode upward from their hips to complete the tackle. If they are told to hit from midthigh to the armpit, it makes the strike zone almost impossibly small, especially if the quarterback is moving and the defender is being blocked.  Dilfer offered two solutions. First, make sure quarterbacks are taught not to lock their knee when they plant their foot, which could reduce the damage caused by a low hit. And he said the rules should bore more deeply into the offender’s intent. A late hit would draw a penalty, but he says it is easy to decipher when a defender intends to hurt a player.  “I think if there is clear intent to hurt or it was late, throw the flag,” Dilfer said. “Otherwise, these guys wear pads. If they’re only looking for two things, that makes it easier.”  That kind of change seems unlikely, which means there will be more fuel for debate each week. Perhaps among the players, too.  “At the end of the day, players want to be protected,” said Ray Anderson, the N.F.L.’s executive vice president for football operations and a former agent. “It may not be macho or manly to admit you want protection. I know from talking to coaches and players, they like the emphasis, particularly on unnecessary roughness, the stuff that could ruin careers. It’s not their culture to say anything. But we’re responsible for helping to protect players from each other.”  A version of this article appears in print on October 18, 2009, on Page SP5 of the New York edition with the headline: Roughing Penalties: More, and for Less. Order Reprints| Today's Paper|Subscribe
The N.F.L. has called more roughing penalties on a wider variety of hits this season. Some around the league are not sure that is for the best.