I do say "I feel" a lot, because there are a lot of things I have opinions about. It's just that they are opinions I have formed by logic rather than emotions. Used to express opinion, the phrase "I feel" is really just a matter of semantics.
Thinker's don't not have feelings. They do tend to be more logical feelings. But the two aren't mutually exclusive.
I find myself saying I feel around my friends whom I believe to be feelers and I think around people that are probably thinkers. I hadn't even noticed until recently. I guess I do it to relate more to the person I'm speaking with.
Hey.... You just believe that you dont have feelings and have difficulty knowing your own/separating them from your deductions. We ALL make decisions based on feelings. But Thinkers use the rational/logical answer/deduction. We must not forget that different answers can be rational when seen from different viewpoint. Since thinkers use /try to use objective viewpoint, they speak more of an "universal" language and often come to the same conclusion.
I myself got some personally devastating information recently. Since it shouldnt effect anyhting in my life really, from a logical standpoint, that was what I deduced and held on to. But some days later I started to feel bad with no apparent reason. Self analysis later, I saw a lot of stuff just coming back at me that was "illogical", but still effected me emotionally.
So even if we try to be vulcan mentats -and often believe we are - we are not impervious to feelings. We just try to not give them attention when they interfere with the rational answers. And as defense....
I am quite worthless when it comes to knowing HOW I FEEL. But I can readily read others.....
Both are just functions of the brain and have more to do with behavior than really verbalizations. Thinker's aren't always right just because we use "logic" and such doesn't make us right seeing as our own logic is limited to our own life experiences. So therefore using the words feeling is fairly appropriate when one is unsure.