A recent commenter on a recent word-search question nominated a term as “an even better word for what is trying to be said.” This seems to me to attribute intention to something—a meaning—that is incapable of intention. I have also encountered this same fallacy, as it seems to me, with words such as able and ability followed by passive infinitive, in such a way as seemingly and absurdly to locate the ability in question in the patient rather than the agent. For some reason, passive constructions like “capacity to be [past participle],” and “capability of being [past participle],” which respectively locate the capacity and the capability in the patient, do not likewise bother me in the least:
The 235U nucleus has the unique capacity to be split by a neutron into 89Kr, 144Ba, and three neutrons that can in turn split further 235U nuclei.
But I would never say or write that the nucleus is able or has the ability to be split.
To say that something “can be said” is unquestionably grammatical, and some instances of “able to be said” result from trying to put that into the future tense or conditional mood, as “will/would/could/should be able to be said.” To say that something is sayable is also unexceptionable: adjectives in -able or -ible normally tend to modify or be predicated of the patient.
A Google Books ngram of “able to be said,” “trying to be said,” and “try to be said” shows very low but non-zero frequencies for the former two. A plain-vanilla Google search for “able to be said” turns up (besides a few instances where a comma and right-hand quotation mark separate be from said) a surprisingly high proportion of results from Google books, and a surprisingly high proportion of results that are products of translation from other languages. (Also and less unexpectedly I found among the top results one that resulted from a transformation of “can be said” as discussed above.) Searching for “passive infinitive” in combination with “able” or “try” led me to some on-line grammatical resources, but the only one to discuss this particular problem was a page I had written for my students a few months back.