Which is better coding style?

Is better to code
1. In a way can be readable easily on first sight but maybe inefficient
or
2. That is very efficient and short but more complicated to read and understand

My instructor (a very scary prof) always tells us to go to option #1. Yes you can still do option #2 if you provider enough comments to explain.

But if you do option #1, you will not need to comment alot about your code because your code will speak for itself because of its easy readability.

What do you think?

like how can you make sure your css loads and formats everything before actually displaying the page regardless of browser?
you could put "body{display:none}" in a style tag in the html file and then put "body{display:inline}" in your stylesheet and make sure the link tag for the stylesheet is after the style tag...