superman in H/P was relying on his gear the entire time, he was scared of doomsday and felt the new genesis stuff would save him.... wrong.
owaw superman would have at least lasted longer without the tech on, he used his brain.
yes doomsday has the reflexes, but he also has the durability and strength (that is dynamic) to make his reflexes matter. same as nur
doomsday's speed meant nothing against the radiant cause that was a different opponent, just like in this instance. he will have to adapt to the best of his abilities to another guy who adapts via will on the fly as well, but he can also change his physical might which is something doomsday can't do.