How adjectival can a participle be?

«This book takes theoretical linguistics by storm, moving our understanding of the passive construction onto a whole new level. Samirah Aljohani puts the adjectival passive under the empirical lexico-grammatical microscope, producing numbers which both dazzle and clarify. Inspired science from copious data presented in an accessible style – absolutely brilliant!» (Dr Christopher Beedham, University of St Andrews, Scotland) Most analyses of the English passive (formed with be + V- ed ) claim that