As another reply said, the consensus I read is that you really shouldn't memorize the table of "-.- is K", if you do you'll likely need to "unlearn" it to get any level of speed. The best thing is not really think about the dots and dashes but train on the sound; "dah-di-dah" = K.

It's a lot like how when you read you almost never read every letter, you look at the entire word and that turns into an idea in your mind.