It really depends on where you draw the line. Although the date 1054 is given as the beginning to the schism, in reality communion was maintained by some people in some places longer than that. For example, The Orthodox regard St Sava of Serbia as indisputably Orthodox, not Catholic, and he was post 1054, but Catholics regard him as a saint too. Gregory Palamas was 13 century, but people who know more about it that I say there is nothing objectionable in his writing. My son, who is a Byzantine priest, disagrees.