Last Sunday afternoon, Bay Area violinist Gil Shaham performed an all-Bach program in Dinkelspiel Auditorium. The pieces he played--“Partitas No. 2 in D minor,” “No. 3 in E major” and “Sonata No. 3 in C major"--were ones he's been playing for over 30 years, which explains the blistering speed at which he performed several of the movements.