Richard Cervin's article — the source behind egalitarian lexical claims; problematic methodology

Lynn Cohick's claims trace back to Richard Cervin's article 'Does Kephale Mean Source or Authority Over in Greek Literature? A Rebuttal' — specifically rebutting Wayne Grudem. Cervin refuses to analyze any NT examples of kephale and rejects all NT-specific lexicons, claiming they may be influenced by patriarchal culture, that lexicographers can't determine Greek meaning, and accusing them of not reading extra-biblical sources — though BDAG quotes Plato, Herodotus, and Plutarch regularly.