If you can read Japanese, you might want to take a look at a recent paper by Ayumi Ueyama --
上山あゆみ (2006) 「経験科学としての生成文法―文法性と容認可能性―」, 九州大学言語学論集 25/26 (Ueyama, Ayumi (2006) "Generative Grammar as an Empirical Science---Grammaticality and Acceptability---", Kyushu University Papers in Linguistics, vol.25/26.)-- which directly addresses the methodological point alluded to in my Mayfest talk and elsewhere.