@ Putin, you miss my point and change the subject.
To refresh your memory, my point, to which everything else I said was aimed at supporting was as follows, "Someone who has studied a subject and formed a belief is not necessarily discredited simply because they have made up their mind on the subject. That was my point and the point that it seemed Draug was trying to reiterate."
Thus the reason for asking if the last person worth talking to about the subject of marxism/meninism is a marxist/leninist professor because they are biased toward that belief system. (As you seem so keen to point out about Christianity)
Any religious belief starts with an underlying worldview as I am sure you would agree, however not every individual who espouses that belief began life with that required worldview. No worldview is provable beyond a shadow of a doubt, be it Christianity, Islam, Secular Humanism, Atheism, Marxism/Leninism. And those last three are no less fundamentalist in their championing of their worldview than the religions, despite the fact that the underlying assumptions of those views are no more provable (or disprovable) than the religions. Thus, someone who examined various worldviews and made an informed decision based on evidence rather than blindly following a world view, in my opinion would be a good person to talk to about that worldview, be it Christianity or Marxism/Leninism. (However, for some reason, I don't think you will acknowledge this last sentence at all and will focus on the sentence preceeding this.)
A little clarification as well since you bring the subject up:
"But on the subject of religion you can hardly expect a non-biased answer, since their "Lord" commands them to "spread the good news" at all costs."
"The whole point of Christianity is to absolutely convert everyone."
The first is correct, the second is not. The command as you said is to spread the good news to everyone, but the command is not to convert everyone. Christians were given the task to spread the word. God did not however command us to "convert" people; He's kept that job for Himself, and while He pursues everyone He doesn't force anyone to believe Him, otherwise we wouldn't be having this discussion. Any Christian attempting to do the converting themselves, and against a person's wishes is thus not following the commands of Scripture. We are called to preach and teach, not convert. Unfortunately, there are a significant number of Christians who have this wrong, and have misrepresented what Christ taught.
Now let me contrast with the marxist/leninist view, which as history has shown, is meant to be enforced on people regardless of their belief. The working class is supposed to tear down the rich because the rich are incapable of treating the working class as they deserve, there cannot be equality without revolution. Broadening the argument, socialist policies in general are designed to be enforced because the uneducated don't know what's best for themselves, so the intellectual class, who knows what's best for everyone takes from the wealthy class and gives to the working class, while claiming they are the only ones qualified to have power because they are educated and know what's best for everyone.
Now, you tell me which of these views pushes itself unwanted on individuals in a more sinister manner.. Revolution and/or involuntary wealth redistribution? or telling a miraculous story about a God who became a man, died for humankind's rebellion so humans could be saved from destruction, and letting the world decide what it believes on the subject? (and again I grant you that this is unfortunately not the route that all of what is called Christianity has taken, and that many have used Christ to fuel their own power trip)