The author would like to add acknowledgments to the above paper:

Work on this paper has greatly benefited from comments by Allen Wood, Marcia Baron, and participants at Dina Emundts’ colloquium at FU Berlin, at Tobias Rosefeldt’s colloquium at HU Berlin, and at Dieter Schönecker’s colloquium at Universität Siegen. I also wish to thank Alix Cohen for graciously agreeing to respond to my concerns.

The author apologises for this ommission.