"[Relation Pronoun] + [be V] + [adj] => [adj]" means that certain "be" verb expressions can be left out without changing the meaning, which is definitely true. "be" is like the most common, "default" situation of all verbs, so in certain constructs they can be omitted without any loss of information. The most common example is the relative clauses as you listed. For example, in these relative pronoun sentences, omitting "who + be" leaves the sentence equally clear (if not more). 1. There were many people (who were) stricken with this disease. 2. His wife, (who is) a very nice person, has helped me. The other major case is with participial clauses. 1. (Having been) promoted twice, he is now a mid-level manager. 2. (Being) an efficient person, he did not wait until the instruction came. To me, these sentences sound even better without the "be" participle.

Well I don't think I understood a lot of the code script that you have written like a computer language that represents English grammar , I bet you're some computer code developer :-) However, both your upper versions of the sentences are correct ex. some questions which are relative to the subject == some questions relative/related/relating to the subject (in this position, all; the adjective, the past participle, and the gerund serve as an adjective BUT ofcourse you have to choose in each sentence the one that is best for the meaning of each sentence)