Shanahan said that Cousins has been seeing more repetitions this season, which he feels is helping the player improve his offensive reading.
"He has got to get a lot more repetition," he told the club's official website. "When you're the second team quarterback, normally the second team quarterback is getting very, very few reps during the season. And all his reps are basically working the scout team.
"So to get the opportunity to get some reps with the first unit is something that he hasn't had for a while. He's jumping in full speed and getting as many reps as he can.
"You can get better as a quarterback going through the natural reads. Even though the depth may be a little bit off, some of the plays are a little bit off, just getting those reps does help."
Cousins has played five times in his two seasons so far with Washington.