It is very difficult to avoid this because disregarding information is nigh impossible as you said, but I think the information that you have should be used in order to answer the questions. I believe that even if you know what answer you will get, the point is to answer from experience, instead of preference. If experience states that you logically thought through a situation and considered only what you knew to be true, then you are more likely a T, an leaning towards S undertones. That's why I wish someone would create a test that was more problem solving based. Instead of asking personality based questions.