Was the synagogue a place of sabbath worship before 70 CE?

Before 70 CE there were no separate synagogal buildings and, if there were, they did not serve as places of worship on the Sabbath. These two propositions, briefly stated, have been increasingly argued in recent years. The first, that there were no synagogues in the sense of buildings (at least not in Palestine), was launched by Howard Kee (in 1990). I will deal with it only summarily because it has already been competently and sufficiently refuted by other scholars. The fullest case for the second proposition, that synagogues were not places of Sabbath worship, was presented by Heather McKay in 1994, and I will discuss her theory in more detail.