I recently thought that there should be 10-times rule for good documentation. So, every line would be documented (best if self-documented), every 10 lines (whic

I recently thought that there should be 10-times rule for good documentation. So, every line would be documented (best if self-documented), every 10 lines (which is roughly a function), every 100 lines (a class?), every 1000 lines (a module), and so on until you got to the top of the system. But it's an awful lot of documentation to maintain.