Childress, speaking at the NFC coaches' breakfast during the NFL owners meetings in Orlando, pointed to how much Jackson and Rosenfels learned from playing behind Favre last season.
Childress especially focused his comments on Jackson, who has yet to sign the tender the Vikings extended him as a restricted free agent.
"I think they both evolved and grew even though it might have been in a vicarious way last year with Brett, through him," Childress said. "But I know there was great dialogue and I watched Tarvaris in his games and in his snaps do a great job and I thought he grew mentally, which was as important as anything, in how he approached the game and how he approached practice.
"Really some of the intangible things because there's not statistics for that. I think on face talking to him he'd really admit that it was a great year and you can't put a premium on that. Being around a guy like Favre and growing in our system and seeing how a Hall of Fame quarterback operates our system."
Indications are that if Favre surprises everyone and does decide to retire that Jackson (10-10 as a starter in four NFL seasons) would take over. Jackson was the Vikings' No. 2 quarterback last season.
"If you took it off of last year, yeah," Jackson would be the starter, Childress said. "But we're going to get to the field here before we start next year so we'll just see how those guys have evolved."
Meanwhile, Childress said he had no update on Favre's possible return and clearly the Vikings remain in wait-and-see mode.
"I don't know," Childress said. "Just the same as it has been really. I just don't know. I told these guys before, in this business you have to be able to deal with uncertainty and ambiguity because that's what this is about."
That could continue into the first part of training camp, too, because no one will be surprised if Favre decides to join the Vikings after they return from their stint in Mankato.
"It was a good debate, and we discussed it," Wilf said at the owners meeting in Orlando. "I guess I'm old-fashioned. I like the rules the way they were and whatever the outcome would have been. We'll move on."
"There's a point in here where, I'm told, that on an ACL injury, you feel stronger than you really are," Childress said. "And there's a point where that graft or whatever it is that they do becomes brittle. And you have to be really careful in your third, fourth, fifth month that you're not doing what your body feels like it can do. You have to stick with the protocol. I guess it becomes brittle and it strengthens back up. It's the strongest early and it goes to a spot where ... He's doing as good as he can be doing."
QUOTE TO NOTE: "You know (he's) a good player. I don't know if we're far enough down the free-agent trail here now. He's certainly a guy that's on our board and on our list, as are others. Is there interest? Not right this second. Do I know of him and skills and abilities? Absolutely. And I have a lot of admiration for what he has been able to do." — Vikings coach Brad Childress on the team not having interest in running back Brian Westbrook, who has been released by the Eagles. Childress was Westbrook's offensive coordinator at one time in Philadelphia.