The whole reason manufacturers pay big money to endorse players is so Joe Average will take note of the racquet and go buy one. If TW were to blow the cover off that, it would at the very least be a kick in the nuts to their major suppliers (not to mention a bad move for TW's own sales). At worst, it could be a breach of contract.
It's not worth worrying about. The educated consumer can always find out the truth, if he wants, and the ignorant one is generally just as happy with his product in the end, anyway.