I see this play out everywhere, be it in discussion on the internet, or real life conversation. Person A makes Statement X, and Person B goes on a rant about how ridiculous Statement X is, only for Person A to break the bad news that Person B has badly misinterpreted Statement X. The result is wasted time and wasted breath.
It happens constantly. I'd feel comfortable saying the vast majority of debates I witness consist 90% of this sort of thing, of two people attacking each other for views they don't hold, or for saying things they didn't actually say or mean.
Be charitable in discussion. Language isn't perfect, and we don't wield it perfectly. Make every effort to ensure you understand the other. If they say something that sounds out, take a step back and ask yourself if you are misunderstanding them, and ask them to clarify.
And for the love of God, resist, with every fiber of your being, resist the delicious temptation to misconstrue the other's statements simply because they phrased things in a way that could be carried to absurd places and make yourself appear the victor. We have an unfortunate impulse to want to win an argument, and it often gets in the way of truth.
Remember, truth and understanding is the goal, not winning.
Be charitable. Don't assume. Request clarification. It'll save us all a lot of time and frustration in the end.