I imagine they tested numerous prototypes between 95-99 and it's likely this size with the 23mm beam fulfilled the vision they had of this tour model. The reality is that the difference between 97 and 98 sq/in isn't much at all and if they called it a 98 likely nobody would even notice.
Definitely not. People tend to really blow this out of proportion than it really is. It depends more on the head shape than the actual size of the head, because the sweet spot's distributed differently.