I have never heard Tiger say anything about his tape except that the callus on that joint is painful and that the tape eases the irritation. He stated awhile back that when the summer is in full swing and the humidity goes up, his calluses actually tear.
I have a large callus on the same joint on my right hand, but I have a smaller one on the index finger also. Both bother me at different times. I would imagine that a painful callus could be independent of swing issues and more in line with a person's physiology. What hurts Tiger may not bother you and vice-versa.
Also. I would imagine that Tiger hits a truckload more balls in a week than most people do in a month which would make any sensitive skin situation like a callus, more painful.