Don't you know that any rebuild is a failure unless it accomplishes a dynasty? it's kids, kids, and only kids for first 3-4 years of a rebuild. if they die, they die (as Ivan Drago said) so no use for mature bodies to fill an age bracket we're sorely lacking in.
Except that's not what I'm saying. I wholly agree we need experienced senior players around. Having those experienced senior players allows us to play the kids.
But there comes a point when we can afford to lose one or two of those experienced players to bring in more kids.
Next year Docherty and Cripps will be ready to step up into more senior roles. We have Levi and Matty Wright in the forward line as experience, Kruezer, Thomas, Murphy and Ed Curnow in the guts, and Simpson, ASOS, Rowe, Jones and Docherty down back.
That's plenty of experience, and it doesn't include Gibbs or Rockliff.
Trading Gibbs let's us get Kennedy and Smith and retain our pick 3. It also ensures we do not have to dilute our draft position next year also enhancing our ability to get in more talented kids.
Presuming we can get Rockliff as a free agent, we would be mad not to do it. Heck; I would still do it even if we couldn't get Rocky. We have a enough of a solid core of experience to enable us to play the kids even without Gibbs or Rocky.