Permissions for newly created roles

Hi,
a while ago I made a test with npbr to see what happens to a node where I removed view permissions for some roles when I create a new role.
I gave the new role a " default view permission" and I think in my test a user given this new role could suddenly view the protected node, just like a new role would get a view permission for already protected nodes, too.

I always wanted to write a patch for this because I guess it shouldn't happen this way. Now I planned to start with this patch and tried to repeat the test, but now new roles don't get view permissions to already protected nodes, just as it should be.

And looking at the code I can't see how it should even happen. So now I'm a little bit confused:
Is it possible this was a bug once and you fixed it in the meantime?
Or am I missing a certain configuration where it still could happen that a new role can view nodes which got all view permissions removed before?

If you answer "no" to both, that I have just done my test wrong in the past and apologize for the confusion :-)
I just want to make sure that it can never happen that a new role happens to view a page on that I restricted view permissions, that's why I ask :-)