Yes SJC can handle a 744, the new FIS gate A1C or A1A I believe will handle a 744 in the new FIS, it does block gate A2 from use while on the gate. The new runway once open will be 11,000 feet long so the airport can handle the 744. According to SJC ops the 744 could be approved for SJC if CX does express serious interest in the route. The main issue right now is that CX wants to leave around 0100, but due to the SJC curfew CX would need to retime the flight to arrive in HKG to meet up with connecting traffic.
Although I doubt we would see this till next year at the earliest, I think eventually we will see more long haul out of SJC>
The TSA was created to make the post office look efficient!