>>150237654
I think TDKR's design does make sense. If Bruce persists on being Batman even in his 50s, I'd imagine he'd have no choice but to switch approaches. Relying on speed and agility isn't gonna fly anymore; no matter how much he trains and keeps himself in shape, he'll never be as fast as he used to be. So he'd go the other direction. He'd bulk up as much as his body would allow and rely on raw strength and endurance. He might not be as spry as he used to be, but he has good pain tolerance.
It's like in Rocky Balboa. Raw power was all he had at his age. He just couldn't hope to move like he used to. So he went all out on power. Obviously, even if you use this route, you'll never be as strong as someone half your age, but it's all grandpas like them can reasonably do.