Toots, TF think that too much caffeine interferes with the fat-burning process that takes place in the liver, which slows down the conversion of fat to energy.
I dont touch coffee myself but am a pepsi max freak. Personally, I would just see how you go, maybe cut down one cup a day you shouldnt really notice it that much. It may not effect your weight losses at all and although you wouldnt be following the TF plan 100% it depends how much that matters to you
If the rest of the plan agrees with you it would be a shame not to give it a go cos of the coffee. Try a week with coffee and see what the results are like. Hope things sort themselves out