To reply to senoy’s message in the original thread:
You might be a random guy on the other end of a computer, but I’m debating you not because I want to practice my grammar or give my fingers a workout, but because I am genuinely interested in understanding why you believe whatever it is that you believe. If we disagree, I want to know why, because that understanding will either change my mind if I decide that your arguments make more sense than mine, or it will allow me to explain to you why I disagree with your logic. The problem is, if you are – let’s say – arguing against gay marriage, and I debate you, but later on I learn that you are actually FOR gay marriage, then everything I learned from debating you about the logic of the anti-gay-marriage position is not actually the logic that a gay marriage opponent used to arrive at their position. It is the logic that a gay marriage supporter believes that gay marriage opponents use.
I’m sure you’d agree that a gay marriage opponent most likely disagrees with a gay marriage supporter’s assessment of the opposer’s position. If you have some special insight into the mind of a gay marriage opposer – for example, you used to be one until recently – then SAY SO, because that also effects what arguments you will be making. If you say nothing, then I will have a mistaken impression of what people who oppose gay marriage actually believe, which isn’t fair to them (and yes, despite strongly disagreeing with them, I still want to be FAIR to them), and isn’t helpful to me.