Despite bringing up the rear in the NFC East with a 3-13 record in 2013, there's enough talent on the Redskins for them to be a worst-to-first team in 2014.
With Shanahan's tenure as a what-not-to-do guide, here are five lessons Gruden can learn to make Washington a contender.
The Redskins will only go as far as a healthy RG3 takes him.
It's not to say that Shanahan intended to get Robert Griffin III hurt, but in calling 70 designed run plays for Griffin—as he did in 2012, according to John Keim of The Washington Post—he can be faulted for consistently putting the franchise quarterback in harm's way.
With a slight build, and two ACL injuries already under his belt, Griffin literally may be on his last leg.
While scrambles will probably always be a part of Griffin's game, the elimination of the zone-read would increase the odds that Griffin doesn't become the new version of Michael Vick.
Having a valuable commodity in Kirk Cousins as its backup quarterback, enacting this more cautious approach would allow Washington to deal Cousins for some much needed draft capital.
Near the end of his swan song season in Washington, Shanahan opened up about his relationship with Griffin.
"I was his coach, his head football coach, and not necessarily his best friend, don't need to be his best friend," Shanahan said, according to FoxSports.com.
While Shanahan didn't need to be best friends with Griffin to get the most out of him, respect is something that every coach must demand. And judging from the veiled shots the duo threw at each other throughout their time together, Shanahan certainly didn't have Griffin's.
With NFL players being creatures of habit, the constant questions Redskins players had to answer about the tumultuous relationship of their coach and quarterback had to serve as a distraction.
The type of turmoil that engulfed Washington in 2013 simply isn't conducive to winning.
With Ryan being the only coaching survivor of these failed tandems, it's safe to say that Gruden's job security will be tied to his relationship to Griffin.
With Shanahan gone, Haslett has the freedom to run Washington's defense.
Despite earning his keep as an offensive mind, Shanahan was heavily involved in a Redskins defense that was supposed to be directed by Jim Haslett. The results weren't pretty.
Washington finished no better than 21st in scoring defense in the four seasons under Shanahan.
I’m excited after talking to Haslett about the possibility of him being able to just run his defense without anybody in his ear telling him what to call or what not to call. No disrespect to Mike Shanahan, he’s a great coach, but he liked to micromanage things. He kind of liked his hands on everything.
Judging from his decision to retain Haslett, Gruden believes that Haslett can indeed turn around Washington's defense.
Boasting a top-10 offense the past two seasons, an improvement on defense could vault Washington into playoff contention in Gruden's inaugural season.
The Redskins offense was bland and predictable at times in 2013. Griffin's comments at the postgame press conference following a Week 11 loss to the Philadelphia Eagles highlighted this fact.
"They did a good job of scheming us up. They kind of knew what was coming before it was coming and like I said, that is disheartening, Griffin said, via PhiladelphiaEagles.com.
While delegating is a trait that the best head coaches have, Gruden was hired because of his work as an offensive play-caller in Cincinnati.
With new offensive coordinator Sean McVay relaying to John Keim of ESPN.com that Gruden will indeed be calling the plays, it appears this won't be an issue going forward.
As long as Griffin remains healthy, you can expect Washington to boast one of the NFL's top offenses under Gruden's direction.
Allen should be the chief decision maker when it comes to forming Washington's roster.
Owner Daniel Snyder gave Shanahan a large say in personnel decisions and, as expected, the Skins were marred by bad acquisitions in his tenure in Washington.
Hall of Fame head coach Bill Parcells famously said back in 1996, in regards to coaches picking their players, "if they want you to cook the meal, they ought to let you buy the groceries."
But in today's NFL, the results indicate that the head coach can't put on the general manager hat as well.
Mike Holmgren, Parcells and Shanahan are just a few examples of this very point.
Ultimately, Gruden wasn't hired because of his eye for talent, that person would be Bruce Allen.
While Allen should be cognizant of the type of players that fit Gruden's system, he should have autonomy in building Washington's roster—that's right, just sign checks, don't make decisions Snyder!
With an experienced decision maker like Allen calling the shots, the Redskins could avoid the Albert Haynesworth-type signings that clogged their cap sheet in past seasons.