"We had a lot of games last year that were really close, particularly early on," April said. "I just believe if you have dominant special teams, you're going to win all of those close games.
“You don't always win the game because of your special teams or lose because of them. But if you're dominant, there are approximately 30 [special-teams] plays [in a game]. And all 30 of those plays involve field position or points.
“It's kind of like the house in Vegas. If you've got the odds in your favor, at the end of the night, you're not going to lose. You're going to win. If we could've increased the odds of us winning those  plays, we could've been a much better team."
April is determined to increase those odds this season by getting much better production from his return game than a year ago, when the Eagles didn't have a single kickoff return longer than 33 yards and had only eight punt returns that gained more than 8 yards.
April, who is regarded as one of league's top special-teams coaches, blamed himself more than his players for the Eagles' kickoff return problems in 2011.
"I don't think it was the players," he said. "It could have been the scheme. But I think it was more the preparation for the scheme and maybe some misevaluations on how to utilize that scheme.
“Dion is a good enough returner, and I think we had good enough guys, tough enough guys [blocking]. The responsibility is on me."
April said he did a poor job of adapting to the new league rule that moved kickoffs from the 30- to the 35- yard line. The touchback percentage skyrocketed from 17 percent in 2010 to 45 percent last year. A significant portion of the rest of the kickoffs went into the end zone.
"We didn't do as good a job of practicing coming out of the end zone as we should have," April said. "There were a lot of kicks that were 4-5-6 yards deep [in the end zone] and we didn't time them up well enough.
“The deeper balls killed us. And most people kicked it deep. Not only did they move the ball up [to the 35-yard line], but it seemed like every kicker got stronger. But that's on us, because it was the same for everybody. Everybody had the same rule. We weren't at any disadvantage."
It remains to be seen whether Lewis will hang on to the kickoff return job. While April wasn't really critical of Lewis, he said there will be an "open competition" in training camp and the preseason for the job.
"The results weren't what they should be," he said. "That's not on Dion. But we've still got to get better production."
Lewis will be pressed by rookie fourth-round corner Brandon Boykin, one of the top kickoff returners in the 2012 draft.
"He's definitely going to get an opportunity," April said. "And there are some other guys who have done it. Mardy Gilyard has done it. Chad Hall has done it. Damaris Johnson has done it. We've got to be better there this year."
Despite his poor numbers last season, Jackson is one of the league's most dangerous punt returners. He returned four punts for touchdowns in his first three seasons. His walkoff touchdown return against the Giants in 2010 was one of the most memorable moments in franchise history.
But the Eagles are worried about the effect returning punts could have on his day job as a wide receiver. They hope to find someone else to be their primary punt returner this season, and then use Jackson only when they think it's necessary.
"DeSean will return some," April said. "He's got the ability at any time to make a play and turn the game around. I don't think we're not going to use him. But I just don't know if he'll be the primary guy. We want to use him mainly as an offensive weapon, and hopefully find a guy that can do what he can do [as a punt returner].
“With a guy his size [5-9, 175], there's some wear-and-tear issues. He's a guy who does a lot of running. Most of his routes, he's not running the three-step hitch. He's stretching the field. We've got a lot invested in keeping his legs replenished.
“If we have somebody [else] in that area that can replace him, that's a wise investment. Then we can parlay his ability to be explosive and spry [as a receiver]."
While it's early, the leading candidate to replace Jackson right now is undrafted rookie cornerback Cliff Harris. Two years ago, Harris returned four punts for touchdowns at Oregon and averaged 18.8 yards per return. He was thrown off the team last year after being cited for possession of less than an ounce of marijuana. A few months before that, he was cited for driving 118 mph with a suspended license.
"He's a phenomenal punt returner," April said. "He's very much like DeSean, he really is. He reminds me of DeSean when I watched DeSean at Cal. Really, really explosive. Once they get going, they can pull away. We really want to see him in the preseason. We're going to give him a chance to make the team. And make it as a punt returner." n
Contact Paul Domowitch at firstname.lastname@example.org. Follow him on Twitter @PDomo. For more Eagles coverage and opinion, read his blog at www.eagletarian.com.