Head coach Mike Shanahan is fortunate that his team is playing an opponent that the Redskins can beat quite easily regardless of which rookie quarterback starts.
Even if Griffin is close to 100 percent healthy leading up to Sunday's game, he should not start because there is no reason to risk further injury to his knee.
Who should start at QB in Week 16?
Cousins played well in the Redskins' 38-21 victory over the Cleveland Browns in Week 15. He completed 70.3 percent of his passes for 329 yards with two touchdowns and an interception.
Cousins is more than capable of leading the Redskins to victory against an Eagles defense that has not played well in its last 10 games, nine of which were losses. Philadelphia lost 34-13 to the Cincinnati Bengals last Thursday, and scored just one offensive touchdown, in addition to five turnovers.
All the Redskins have to do to make the NFL playoffs for the first time since the 2007 season is win their final two games.
The Eagles game will not be incredibly easy because it's a matchup with a division rival, but it would be very surprising if Washington lost—no matter who started at quarterback.
However, the Week 17 season finale against the Dallas Cowboys will be an extremely important game, and the winner will almost certainly clinch a playoff berth if each team wins this week.
This is the game that Griffin has to be fully healthy for because the Cowboys are playing very well right now and have excelled when their season has been on the line.
They aren't making the late-game mistakes we are used to seeing from them over the last few years, and quarterback Tony Romo is playing at a very high level and not turning the ball over often.
Washington barely defeated Dallas 38-31 on Thanksgiving despite having a 28-3 halftime lead, and now the Cowboys are a better team than they were then.
Griffin threw for 304 yards and four touchdowns against the Cowboys, and there's no reason why he should fail to have a similar performance in the final week of the season.
Shanahan might be able to play Griffin this week if he's cleared by doctors, but the right decision would be to start Cousins against the Eagles to ensure that Griffin is fully ready for a Week 17 showdown with Dallas.