One other thing that came to my mind: if you add "that" to the english phrase (it is true /that/...) I began to think about using the verb {teH} to say "it is true that..." like {Sopta' 'e' teH}. But that does not work; we know that {'e'} is used with verbs of thinking or observation like "see", "know" etc. I'm sure {teH} is not one of that kind, so that does not work. (although it would nice to have)

More importantly, 'e' has to be the object of a verb, and teH does not take an object without a -moH attached to it.

The advice in The Klingon Dictionary that sentences-as-object primarily use verbs of thinking and observation as their second verbs must be taken with a grain of salt. We have tons of examples of sentences-as-object that don't follow that advice. For example, I count nine uses of sentence-as-object in The Klingon Way (not counting multiple instances in the same saying), and of these only two could be said to be remotely about thinking (tul and Hech) and one about observation (Qoy). Maybe you could argue that wIv represents thinking about a choice, and maybe you could argue that tIv is about thinking of enjoyment, but we're opening up the meaning of "thinking or observation" pretty widely, and we still have the verbs chaw', mev, and baj to consider.

I don't think Okrand has had that particular bit of advice in mind when crafting sentence-as-object constructions subsequent to TKD. I think it's more important simply to keep the second-sentence concept relatively simple. Don't try fancy tricks with these sentences. If you get to a point where you're not sure if you can do something, you probably shouldn't.

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SuStel
http://trimboli.name