GREEN BAY, Wis. -- Mike McCarthy didn't want to talk about it. Asked about his philosophy on assistant coaches -- how much blame they deserve when a player or position group underachieves, and how much responsibility the players bear themselves -- the Green Bay Packers 11th-year head coach dismissed the question.

"I can't give you a percentage," McCarthy said before changing the subject last week, when he introduced four new/promoted coaches on his staff -- running backs coach Ben Sirmans, tight ends coach Brian Angelichio, wide receivers coach Luke Getsy and assistant offensive line coach David Raih.

Later, though, in response to a question about running back Eddie Lacy's weight -- and whether Sirmans' primary job will be to make sure Lacy slims down in order to ramp up his production to its 2013 and 2014 levels -- McCarthy said in part, "The position coach is ultimately accountable for the performance and the training of their players."

Presumably, Lacy's weight problems and drop in productivity -- Lacy is in the process of trying to lose the roughly 30 pounds the team wants him to drop this offseason, and after back-to-back 1,100-yard seasons he had just 758 yards last year -- led directly to McCarthy's decision to fire running backs Sam Gash, which in turn led to Sirmans' hiring.

And if that's the case, Richard Rodgers' limited improvement in his second season likely factored in tight ends coach Jerry Fontenot's dismissal as well.

Although Rodgers caught 58 passes (second-most on the team) and tied with James Jones for the team lead in touchdown receptions (eight), he did not make as big of jump between Year 1 to Year 2 as McCarthy believes is absolutely vital to the team's draft-and-develop program. Despite his 61-yard touchdown catch on a Hail Mary to beat Detroit on Dec. 3, Rodgers finished with only 510 receiving yards, averaging a mere 8.8 yards per catch.

Now, the job falls to Angelichio to get the most out of Rodgers, a 2014 third-round pick from California who caught 20 passes for 225 yards and two touchdowns as a rookie.

"Rich has some skill set that you like," said Angelichio, who has watched extensive film of Rodgers while living in a Green Bay hotel since joining the staff. "I'm continuing to evaluate and go through that as we do the cut-ups. Obviously, he was a productive player last year. … He's only played two seasons in this league. He was thrown right into the fire and, to his credit, he's done a good job with it."

In Cleveland last year, Angelichio coached Gary Barnidge, who'd never caught more than 13 passes in a season -- and ended up catching an astonishing 79 passes for 1,043 yards (13.2-yard average) and nine touchdowns.

Although he downplayed his role in Barnidge's emergence -- "He was given the opportunity to be the guy and he took advantage of it," Angelichio said -- you can rest assured that the tight end's play caught the eye of McCarthy, who didn't know Angelichio before hiring him.

McCarthy has long said that his offense functions best when it has a tight end that can stretch the field -- like the way Jermichael Finley used to.

"Philosophically, to me, to have a successful passing game you have to have big targets that can turn through the middle of the field, whether it's a tight end [or] a big receiver," he said after the Packers' season-ending playoff loss to Arizona.

Angelichio's development of Rodgers and holdover young tight ends Justin Perillo and Kennard Backman or any offseason additions will be important.

"Certainly when you look at any offense, the advantage of the tight end being able to get down the field certainly helps," Angelichio said. "Because it gives you a chance to get matchups on linebackers or safeties and if they use a safety over the top that means Jordy Nelson's outside or Randall Cobb's outside and those are all win-win matchups. I think in any offense you'd like that, certainly. But if you get that, you certainly have an advantage to use as far as matchups."