I just did a mental substitution for the word "stochastic" and moved on, since it wasn't the main point of the article. But you are correct. Computing the future states of a chaotic system, given the same initial conditions, will produce the same results every time but change the initial conditions ever so slightly and you have no guarante where you will end up next (unless you picked a state from a previous simulation, that is... But that's cheating;) )