Interesting. That sound like what is most helpful for a new developer is any information which would help him to do the mapping, to "connect the dots", is this correct?

I am wondering if it would help to have a document which takes the whole list of requirements from the requirements specification, and explains how each requirement is realized in the code. (Or of course, if it is still missing, in which way and where it is missing, and what would need to be done to add it).