I found the thread here http://paizo.com/forums/dmtz59u5?Synthesist-saving-throws#1 but I have a caveat. While the synthesist Fused Eidolon ability replaces the class's eidolon ability, it does state that in all other respects it acts just like the base ability. Well, the base ability says you get certain saving throws as dictated by the Eidolon Base Statistics table. Has a ruling come since February if the synthesist gains both his own and the eidolons save bonuses?
I think I'll take this as a no. :)