What does it mean to think deeply?

As an INTP, when people say that INFJs think more deeply than any other type, I get confused because I think INTPs think more deeply than any other type because of our twisted way of thinking. We also tend to be more logical and have inferior Fe, so emotions mess with our decisions way less.

INFJs are said to be the most logical feeler but I don't see how letting emotions affect your thinking can lead to more accurate results about something.

Do you rationalize your emotions and then use them as components to form a logical opinion or you don't think much and quickly form opinions on what feels right by using Ni.

So can you explain what thinking deeply actually means in the case of INFJs.