[ Will is smart. He's smart not to attack and he's smart to frame his words the way he does. It doesn't mean Walter isn't suspicious of this shift in tone of their conversation, but he also doesn't feel it necessary to attack. Discussion. They're having discussion. And the question asked is a good one. ]

It depends on what is being changed, I suppose. When you look at the grand scheme of things, no matter what you do -- it's useless. You prolong the inevitable.

[ He thinks about both Jesse and Hank, and how as soon as they experience the future -- when they come back, it doesn't matter what Walt does. They will both hate him. ]

But change will happen regardless because of the nature of this world. If your powers don't morph you into something else, the people in this world might.

[ A nod to Chilton and what Chilton is attempting to do and likely will continue to try and do, long after Walt is gone. Because the one solid truth is that Walt expects Chilton to outlive him in this world. ]