There was a clone, madara hit it, it went poof then he was stabbed in the back. Neither of them were moving at any impressive speeds at the time of this occurence so it would be ridiculous to say hashirama was moving at ftl speeds so madara couldn't possibly react.
Its more like this. A Clone, Madara was distracted and Hashirama "used Kishimoto logic of stealth action" stab. That's how all substitution feats work in general.
Its more of a stealth feat than speed. Does this mean substitution can't be evaded? No.
Kenpachi nor anyone in bleach need current feats to prove they are faster and more durable than anybody in naruto. The only durability hashirama has is perfect susano'o and he isn't edo so he can't hold it forever where as kenpachi and byakuya can fly and have outrageous stamina.
Right because we all know Kenpachi has displayed speed close to BM Naruto or even Juubito. Unless you are seriously on a major leap of faith scaling of Flash steps which are more visual "Wow" tactic by the author.
Or its the other logic like gamefaqs that Kishimoto inconsistencies negate all Naruto speed feats and say bijuu balls aren't even heavy.
Whatever it is. Lets go by case by case basis.
This is going back to Madara's reaction feat. We know hypersonic but that's all.