Is there a printed map / tree / graphic of a sample array(s) during each phase?
Devel is a good place to start. That will make the function dpm() available to you. This will allow you to print out arrays in an extremely user friendly visible way. If you're doing any sort of development you should really look into this module. I know when I'm trying to figure out what's being called for a given area I often use the combination of dpm and debug_backtrace.

There's also a theme developer that relies on Devel that you can you to see a back trace of functions.