Question: why, for grub2, grub.cfg is tested for "automatically generated" header?

[cova-fe]

Sorry if my question is silly, but I'm a a bit puzzled. I'm using genkernel to create and install my kernels. I tried to use eclean-kernel to remove old kernels and I noticed that it does not find any kernel referenced in grub.cfg (believe me, they are :) ).
It seems that is due to the line 30 of grub2.py, where the file is tested for the header "...DO NOT EDIT THIS FILE...". Is this the intended behavior? I'm not sure why this is done, as basically this could lead eclean-kernel to remove all kernel files even without -d parameter, that does not seems to be really safe.