A very old review from the mid to late '80s. But my memory of him is that he helped explain topics to you from a different angle than how you first approached it. An important way of thinking, in your formative years.
This guy was a horrible teacher in Math and Computer Science. You could open the text book, copy it onto the board, and place a Mr Goalen life size cut out at the front of the class and have the same results. He was unable to explain anything, he would just keep writing out examples and not explain why or how the equation worked. Then there was his wonderful personality...
Used to yell and scream at students in anger, I remember hearing his voice echo down the halls in rage. Never felt comfortable with that.
Based on when I had him in the 80's: He caused some stress. He definitely challenged you, which made you think even harder. He brought the best out.
paid more attention to those who understood what he was talking about rather than help the ones that needed it.