From posters who are much more knowledgeable than myself, I've read that Head used the Ti Radical mold for this frame. Maybe the original mold was no longer available, and/or it was just more convenient to use what they currently had on hand? I don't know.
Agassi's own frames, though, weren't the same as the original Trisys frames that were available on the shelves. He used a custom 20x21 pattern.