In my opinion this only shift the problem from coding clean code to handling hundreds or thousands of simple and small source files. This will make much more complicated to handle a large project because everything is scattered in such an extend that a developer spend more time searching thru the include list of files than understanding what the code is actually doing. Implementing complex functionality is going to be a nightmare and the end, everything is going to be merged in a single translation unit anyway. But this is just my personal opinion..