Around The NFL week 2

[JoeRedskin]

Didn't see it happen but, if it did, they should be penalized. The players fined and the team either fined or forfiet a draft pick. B. Ryan's teams were famous for it and it is why they instituted the rule that a stoppage for injury in the last two minutes costs you a time out.

The rules allow stoppages for "injured players" not fake injured players:

"TIMING: ... 4. The Referee will allow necessary time to attend to an injured player, or repair a legal player's equipment."
NFL Rules

Inside the last two minutes, you get one extra "mulligan" for an injured player but after that, you are penalized 5 yards for clock stoppages caused by injuries.

"TIMING IN THE LAST TWO MINUTES: ... 2. A team cannot buy an excess time out for a penalty. However, a fourth time out is allowed without penalty for an injured player, who must be removed immediately. A fifth time out or more is allowed for an injury and a five-yard penalty is assessed if the clock was running. Additionally, if the clock was running and the score is tied or the team in possession is losing, the ball cannot be put in play for at least 10 seconds on the fourth or more time out. The half or game can end while those 10 seconds are run off on the clock."
NFL Rules

Faking an injury to stop the is not the same as the quarterback running the clock down or the ref dropping the ball. In the first case, the play is permitted and explicitly allowed by the rules:

"TIMING: ... 6. Time between plays will be 40 seconds from the end of a given play until the snap of the ball for the next play, or a 25-second interval after certain administrative stoppages and game delays."
NFL Rules

Teams may use less than the 40 allotted seconds but they are not permitted to use more and are penalized for doing so. As to the ref dropping the ball, it's an unintentional act by an non-participant in the game and is not an attempt to gain an unfair competitive advantage by one side or the other.

At a minimun, faking an injury to stop the clock or give your team a breather - being a deceitful act to gain an unfair competitive advantage in the game - should be an unsportsmanlike conduct foul with a resultant 15 yard penalty if caught in game.