The first 11 miles gets me to Rengstorff and Middlefield. It looks like I can cross 101 at Rengstorff, and make my way up to 84 at the shore via either the Stevens Creek trail and/or a couple of local roads. Unfortunately I can't find the map on my work computer, I have it at home, so I can't remember the exact route -- but it looks very easy to follow and low traffic. Then once at 84, there is a bike path that follows 84 west, then 101 north for a ways, and joins up with the trail that goes by the San Carlos airport, with maybe only a little bit of time on frontage roads.
As you mention, following middlefield is another option but it looks like it gets pretty high-traffic (and lots of stoplights) in Palo Alto.
Hoping to do it for real next week.