Here is a link to my updated paper on 'that'-clause complements: Constructing Attitudes.
Abstract: The singular term theory maintains that that-clauses are complex singular terms which designate propositions. Though extremely well-supported, the theory is endangered by the existence of oblique that-clauses; that is, that-clauses occurring in what appear to be non-argument positions (e.g., ‘Lola was upset that Slick Willy had all the fun’). In this paper I argue that the best solution to the problem consistent with the singular term theory, invokes a construction-based grammatical theory. Such an approach challenges traditional views of semantic compositionality by rejecting a central dogma of semantics, namely, that linguistic constructions contribute only trivial logical or quasi-logical information to semantic interpretation (e.g., function-application relations).