And there are time-scales of processes used or needed by intelligent systems that do not speed up easily. The prime example is insight into physical processes. Even if you can infer all there is to infer from an experiment - you still have to wait for the experiment to complete. Some physical experiments are inherently slow. Consider the simple example of observation of the astronomical cycles. You just can't speed them up. Luckly humans have by now observed most of them. Granted, sometimes you can infer the whole cycle from only parts of the cycle. And then many experiments need physical construction of experimental apparatus which also cannot be sped up arbitrarily.