Plenty of nay-sayers had written Dagg off in 2015, closed his case file as an All Black and were adamant he'd never again play test football.
He returned to action in 2016 with seemingly more pace, more awareness and less inhibition to earn an All Blacks recall and re-establish himself as a regular in the back three.
His career revival was a salient lesson to not be hasty in making definitive judgement.
But Savea is not Dagg - different athlete, different skill-set, different player. They are an apples to oranges comparison.
Dagg is a kick and catch player. Speed and agility are a part of his offering, but not the fundamental component and as a result he can become a better player with age.
It's repetition that builds confidence and accuracy under the high ball and its experience that builds game awareness of knowing where to kick, how to chase and where the space is to exploit.
Kick and catch players such as Dagg have longevity as proven by the likes of Ben Smith and Cory Jane who respectively reached 30 in the best form of their careers.
Savea, on the other hand, is a power wing. His game is built, almost exclusively, on his pace, footwork, strength and ability to beat players one-on-one. He's a finisher, a hit man at the end of the line who has to be able to convert half chances and increasingly not even that much.
In 2015 and 2016 when Savea was struggling for form, there was an immediate and rational explanation - he wasn't fit enough.
The All Blacks coaches worked on the theory that if they got Savea back into the right physical shape, his game would return.
They were right. Savea didn't play consistently well one he was better conditioned, but he had sporadic performances that were as good as any he had ever produced.
He still had it. But now a different reality may be at work.
Savea has stayed on top of his conditioning. There are no immediate, major gains for him to make on that front.
What he's been showing is maybe all that he has and perhaps there are two things working against him.
The first is that power wings have a notoriously shorter career window. If there is a pattern, it is that explosive wings tend to emerge at a younger age and lose their edge younger, too.
The likes of Joe Rokocoko and Sitiveni Sivivatu were stars at 21 but not genuine test players by the time they were 27.
They lost a fraction of pace, a little of their agility and acceleration and their try-scoring dried up. The reduction was minimal but what makes it appear more severe is that younger, faster players come into the game and convert more of those half chances.
Is this what has happened to Savea? Has he lost one per cent of his physical offering at a time when Rieko Ioane and Waisake Naholo are in their prime?
Has Savea hit that invisible barrier power wings so often do and is he now destined to find that no matter how hard he works, nature will be working harder against him?
The next few months will provide the answer and the magic of sport it's infinite capacity to spring a surprise.
