What does he bring over Pat or Michelle?
Understanding everything it takes to design a chip, after spending 15 years leading the company that makes software tools for chip design, perhaps.
Cadence Design Systems, that is. I worked there for a couple of years on computational lithography/optical proximity correction software that we licensed to TSMC and Micron. If you don't know about Cadence, well, you don't know about silicon.
Some of the biggest EDA tools come from companies that use them for a reason (NX by Siemens, CATIA by Dassault, ...).
Those are the same reasons that make Lip-Bu Tan a great choice for the position.