I heard that Jack is a lot quicker as well so you can't just run away from him as easily. If he's on your tail and you're nowhere near a safe room you are fucked basically.
That is true although you're not "fucked" as you can avoid getting hurt by blocking and dodging. But if you just try to run down a straight line with no plan he'll constantly spin you around. There's no point in Madhouse where it's "Whelp. You've lost now." you can always survive, it's just hard if you're not good at the game.
I think what Dark Souls fans refer to as "Git gud"
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^ Hey now that's completely unfair! http://i.imgur.com/yPw05Ob.png