Have we ruled out simple substitution unwisely?

[eggyk]

I would say that everything said that most things from this thead has been already tried.

You can check the transcription of Prescott Currier. He several treats groups of signs as single entities like it was suggested here: 
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It increases the entropy but makes the words very short, many words will have only 2-3 symbols.
And it didn't help to solve the manuscript.

That's different to what i mentioned, isn't it? In each case the groups of signs are considered to be a single entity. 

I'm stating that groups of signs could each be a variety of different entities, in different configurations, exactly like minims.