Wow this thread just keeps getting deeper. I still go back to the CYA and KISS methods of life. I don't care who you are, who you are flying for, etc.. I bet every single one of you have done some "illegal" flying either knowingly or completely ignorant of the fact.
I think the real key to this topic is to spread the word, help educate others, and share operational experience. Deep down, we all know that the "on-call" is a very sensitive term in the 135 world, because it's the way the business is done for the most part. Just don't be a schlup about it, figure out a way to make it work in your operation so it will meet the definition.
Fly safe