What I'm saying is that making Juggs grunt in pain does not necessarily mean one is capable of actually wounding him. There is not a single drop of blood indicating real damage. It's almost akin to Superman grunting when he's lifting a truck. Meaningless. Superman won't tire from that, just as Juggernaut won't, as seen in the next panel.
Same cannot be said for the Hulk, who was spewing out blood from his mouth and nose after each strike, despite his durability being higher than ever - as noted by Wolverine himself, who has fought almost every version of Hulk - including (but not limited to) Savage, Fixit, Professor, Bannerless and more.
Stoic is just funny with that hilarious belief of his that Green Scar could tap into WBH energy reserves any time he wanted.
He couldn't, he didn't even know he had it in him... it took a betrayal from Miek, Rick getting stabbed and realizing his whole revenge-quest was all for nothing that made him go World Breaker.
He wasn't able to control it in any way. Not during the original WWH storyline, at least.
If anyone could draw on more power, it was Juggernaut, actually... admitted by Hulk's creative team themselves in the past in their own letter column... and even if Hulk was somehow able to bypass his durability, then it's a damn good thing Juggs was shown to be capable of extremely fast regeneration... or fighting as a bare skeleton while not even at full power.
Banner knew BFR was his only option, we see him advising Skaar to use the same tactic later.