No, it's not the exact `if` condition from above - in particular it's not immediately obvious that the non-existence of `block_corosync_file` means it's the first `chef-client` after a clean reboot, so yes I think it really is worth a comment.  Maybe it's all obvious to you, but a) you wrote it, and b) you're very smart ;-)  I honestly had to think hard about this, and even had to write a boolean truth table before I felt sure I understood it.