In terms of server performance, which is better:
1) split code through several php files for easier reading.
2) try to contain similar code (functions and classes) into a reduced number of php files.

Does file count negativly impact server performance? Is it bad practice to use a lot of include and/or require?
Also, I've read that include_once has a bigger impact on server performance, so should it's use be limited to absolute musthave situations?

I'm asking because when at the early stage of module developement, I could easily break the code into smaller pieces spread out to several php files, or try to condense the page count.
I've also been reading through 2.3 on the SVN and see that Skalpa breaks up the code into small peices spread out through several pages.

Thanks