Ummm yeah. Although as you get into it you find out there are plenty of variations even within those punches.
For example the 1,2,3 may be thrown (almost always like this as a beginner)as fast as possible sequentially in order to overwhelm another beginner. But a more experienced fighter may put a slight delay into the sequence if he notices, for example, that his opponent skips over wide in one direction or another. In that case he may just delay his right by an extra 1/10th of a second and throw it more "crossed over" to hit the guy on his slip to his opponents right.
