I tried to edit the core of WP before… missed up everything back then… lool
Here is what I tried now…
I fetched the definition of all needed functions manually and copied them literally into my new home2.php …
As u said, get_header() is in “wp-includes/general-template.php” indeed (so as get_footer())
Sadly enough, those two functions are also using other wp function from other php files inside wp-includes!
Sooooo…. I continued copying (load-template(), …etc)… until I reached those two functions, require() and require_once(), and got long-description errors….
So I called it a truce until some other time :/