General Philosophy on PHP-GTK

When we convert extension (and even GTK itself), is the goal to get the 100% the same or can we modify methods for convinience? For exmaple, I was thinking about the GtkEditable insert() method. Currently it takes two parameters, string and position. Everywhere else where the insert word is used in context it used to insert data from beginning and separate methods exist to append data to the end. Therefore, changing insert() with only parameter to set position to 0 and introduce GtkEditable::append() . There's no BC problem (because the second parameter to insert() wasn't optional). Comments? - Markus