If I recall, Watson was fed the whole text of the answer as soon as the other contestants could see it. Personally, I thought it would be fairer to have it do speech-to-text and/or OCR to level the playing field.

But I suppose these constraints are just targeting the machine's input mechanism and not its actual reasoning ability once the answer is read. I'm curious how Watson at the time could handle a particular category that Ken dominated: "Initials to Roman Numerals to Numbers" [1]

[1] https://youtu.be/PsQ_mT5YSvg?si=8L9uKJj1hpYU_kuf