"The experience I had here - meeting guys from all across the United States, learning from them and the coaching staff and just being here on campus - was the experience of a lifetime."
Allen has played five NFL seasons since leaving Knoxville and he enjoyed every one of them. Still, the pro experience doesn't compare with the one he had on The Hill.
"It's night and day," he said. "It's still fun but playing in front of 108,000 on Saturday, then playing in front of 67,000 on Sunday ... it's a big difference."
After a standout career as a Vol defensive back, he was taken by then-Miami Dolphins coach Nick Saban with the 16th pick in Round 1 of the 2006 NFL Draft. Allen quickly discovered that the color and pageantry of college ball are missing in the pros. Whereas the college game was about pursuing a passion, the pro game is primarily about doing a job.
"I'm pretty sure most guys in the NFL would say the atmosphere is the biggest difference," he said, "along with the business aspect of it, as well."
The former Vol got to experience the business aspect of pro football up close and personal last season. Despite posting three interceptions as a starting cornerback in Miami's first seven games, he was benched for Game 8, then released. Signed by the Houston Texans, he recorded three more interceptions for them to finish the season fifth in the league with six picks.
Another difference Allen has noted between college and pro ball is the time spent preparing for each game.
"It's all about matchups," he said. "In college you can get away with not watching much film and maybe not get exposed. If you don't watch the film (in the NFL) and don't watch your opponent, it's easy to get exposed."
Given Allen's love for alma mater, watching the Vols suffer through two head coaching changes in football and one in basketball over the past three seasons has been terribly disappointing.
"There's definitely been some changes - some for the better, some maybe not for the better," he said. "At the end of the day - regardless of whether it's football, basketball, baseball, track and field - I want to see everybody succeed and do well here at Tennessee. We're one big family. That's what I truly believe. I enjoyed watching the women's softball team win the SEC championship."
Alhough Vol football is down at present, Allen believes it will be back to competing for championships before long. He bases this belief on his high regard for head coach Derek Dooley.
"I've known Coach Dooley for quite a while now. He was the tight ends coach my rookie year in Miami," Allen said. "I feel like he's a great coach. I feel like he has the ability to take the team back to where it needs to be."
"He's energetic. He makes sure the guys are doing what they need to do, on and off the field, in order to be successful."
You need plenty of quality players to compete in the rugged Southeastern Conference. No one knows that better than Allen, a native of Muscle Shoals who was rated the No. 1 prospect in Alabama as a high school senior when he picked the Vols over the home-state Tide in 2002.
"It starts with recruiting," Allen said. "I felt like the last couple of years we haven't been recruiting as well as we needed to. I feel like he (Dooley) did a heck of a job this past year, going out and getting some high-profile players. We've got to steal a few players - pick up some guys we weren't expected to get - then get 'em on the field and give 'em some experience."
Allen believes Dooley's emphasis on character and accountability will pay major dividends in time.
"That's going to be big," he said. "You've got to be accountable. You've got to know that next man beside you is doing his job. There's 11 men on the field, and you've got to be accountable and dependable. If one man isn't doing his job, there's going to be a busted play on either side of the ball.
"And character speaks for itself. You've got to have good-character guys. It all blends in together, when you're talking about character, accountability, dependability ... they're all in the same family."