(tu'HomI'raH also seems like it might be a stronger sentiment than lI'be', since it's a very long root word, and Klingons tend towards conciseness. Even lI'be'wI' would be shorter. I feel like something's uselessness would have to be pretty noteworthy to warrant all those syllables.)

I don't think this is a worthwhile argument to make. It is not the case that words with fewer syllables are less strong than words with more. I'd be more persuaded by an argument that words with fewer syllables are more common than words with more syllables, but even then we have words like Ha'DIbaH and men. For all we know, the etymology of tu'HomI'raH is that there were two guys named tu'Hom and 'I'raH who were particularly lI'be', and got a word named after them. Or maybe the word just sounds more aesthetically appropriate to a Klingon ear.

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SuStel
http://trimboli.name