I would like to suggest that charges such as bad writing, sectarianism, and dogmatism should only be leveled against those with whom one has some degree of political (theoretical, etc) unity. That when leveled against those with whom one disagrees the charges tend to be ad hominem. In fact all three charges are all too often deliberate efforts to poison the wells of discourse.
For the record, as Doug has suggested, Spivak is quite intelligible in conversation and as a lecturer. (By contrast, Gilbert and Gubar, as lecturers, are so opaque and so given to random name-dropping that when they spoke here my wife and I could not bring ourselves to attend the reception afterwards. Their book, however, *The Madwoman in the Attic*, is well worth reading.)
Carrol