It was a long time before I stopped slamming the goalie rod into the wall - but, now that I'm used to it, I like the 3-man goalie. Again, my perspective is from the slow, but powerful Tornado-style game where the ball spends as much time stopped as it does moving; where the ball is only advanced when there is a definite, planned purpose. My objective in goal is to control the ball as soon as possible, set-up and sit motionless while scoping the defense, then either shooting on goal or passing to the forward 3-bar - whether singles or doubles.
This is a big change from when I played on Dynamo and Tournament Soccer and my objective was to shooting the ball as soon as possible. But, it wasn't the change in table that changed my approach, it was a will to compete at a higher-level; to advance from a bar-style game to pro-style game.
Now that I think about it - refraining from banging the walls was something necessary on all the rods, not just the goalie.
The biggest adjustment with the 3-man goalie is leaning to cover the holes at either end of the goal to prevent slop. Since the goalie's center man doesn't reach as far, a key skill is to always, always, always, no matter where the ball is on the table, always be ready to tilt the goalie backwards and stop the slop. This skill is probably worth one or two points a game - every game. Of course in order to do this, you have to learn to move the two goalie rods independantly of each other. In other words - stop moving them as though, together, they make an impenetrable wall - because they don't.
This is just my opinion. Feel free to disagree and/or ignore as you wish.
Paul