(sorry to double post)There is some truth to this. I am always surprised to see how easy it is for even someone with experience to fall into predictable patterns. One of the things I have long taught were ways to encourage your opponent to become predictable, and then take advantage of it.
One easy example... Throw 2-3 belt-high front kicks in rapid succession. Teach your opponent that when your knee comes up, they should bring their hands down a bit to cover their belly. Then switch mid-strike to a high roundhouse. You've taught them to very kindly expose their head. This works better if your chamber for the front kick and the roundhouse are the same.
I guess what I mean is that if a new guy comes into the dojo, you have no idea his physical conditioning, previous martial arts history, or personality type, all of which influence how he will fight. I remember sparring with a fresh white belt and found out the hard way that he had years of boxing experience.