I'm fine with a higher priority, but as of yet I have no reproducibility. As a check, can someone do:
OpenGL.ERROR_CHECKING = False
in one of their test scripts? That might at least tell me whether it's really the glGetError call causing the problem or whether that just happens to show up in the error reports. *Pyglet* showing the problem is just *weird*, there's no common code between pyglet and PyOpenGL other than ctypes and Python. If we have a problem there we're looking at a methodology failure or a problem with ctypes/Python.