It's as much a part of the fabric of the NFL as the forward pass, "Monday Night Football" and the Raiderettes.

It's been around since the advent of the league in 1920, since the dawn of competition between rival cavemen. All of which makes it acceptable, on a certain Cro-Magnon level.

We speak, of course, of cheating.

You're not trying if you're not cheating. Just don't get caught, right? So with the New England Patriots visiting the 49ers today, what better time to examine such tawdry, yet time-honored, tactics?

It was New England, remember, that had a certain taint affixed to its red, white and blue visage as the Patriots won 18 consecutive games entering Super Bowl XLII after they were caught videotaping the New York Jets' defensive signals on opening week.

The sordid affair was referred to as "Spygate," the organization was fined $250,000 and stripped of its first-round draft pick, and Patriots coach Bill Belichick, now known as "Belicheat," was slapped with a $500,000 fine.

And yet the question remains one year later, mostly because new allegations and accusations periodically pop up about when the Patriots began their version of sacks, lies and videotape. Just how much of an advantage did New England gain by illegally taping the opposition's defensive signals during games? There is no consensus.

Many, such as former coaches Tom Flores and Dan Reeves, believe it could greatly affect the outcome of a game.

Others, such as current and former players Justin Fargas, Robert Gallery, Phil Simms and Joe Theismann, said it still is up to players to execute.

"It's impossible," NFL Commissioner Roger Goodell said in a May media conference, "to know the specifics about how much impact it has."

Not really. Well, maybe when you destroy the evidence of eight tapes former Patriots video assistant Matt Walsh produced, as Goodell did, saying there was nothing new on them.

"If you knew exactly what they were going to do, you could then game plan for it," said Flores, the two-time Super Bowl-winning Raiders coach. "It becomes valuable if you know, for example, they were coming with a blitz, a safety blitz. If you knew they were coming with that blitz, you could then go man-to-man coverage on a pass with max protection."

Said Fargas, the Raiders running back: "Maybe that would help the coaches more, as far as what plays they're going to call, what personnel to put on the field. But as far as with the players, we run the plays that are called in the huddle, and we react to the defense that we see out there on the field. I guess that's more of a chess match between coordinators."

Walsh told HBO's "Real Sports" in May that tapes offered a significant advantage in each of the Patriots' three Super Bowl wins, adding the team began the practice at the start of the 2000 season, Belichick's first in New England.

A backup quarterback would learn the opponent's signals from the tapes, Walsh said, and during games would stand next to then-offensive coordinator Charlie Weis on the sideline and pass along the defense's play call.

Both the defense's call and the Patriots' offensive play would be sent from Weis to Drew Bledsoe, then the Patriots' quarterback.

In the 2000 season opener, Walsh said, the Patriots were correct on 75 percent of Tampa Bay's defensive plays after taping the Buccaneers' signals during an exhibition game. Tampa Bay won both games.

"Unless you know exactly what they're doing, it's not going to help you much," said Gallery, the Raiders left guard. "You don't have enough time to figure it out, usually."

Which is why Reeves told the Washington Post a "smart defensive coordinator will wait until the last possible second to send in the defensive signal.

"If that happens, and you don't (steal) the signal until there's eight or 10 seconds left on the play clock, there's nothing you can do."

The day before the Patriots' tainted run at perfection ended in a karmic 17-14 Super Bowl XLII loss to the New York Giants, the Boston Herald reported the Patriots had illegally taped the St. Louis Rams' walk-through practice the day before Super Bowl XXXVI at New Orleans' Superdome. (The report turned out to be false and was retracted, and the paper issued an apology.)

Call The Bee's Paul Gutierrez, (916) 326-5556. Bee staff writer Matthew Barrows contributed to this report.