I guess that reading in lucid dreams was discussed here enough but anyway I'd like to discuss them one more time if you don't mind.

My question would be: Is it true that any text in a dream (f.e. vivid lucid) can't be read twice (or more times) or is it only a myth?

Today I was trying to concentrate on reading in my dream and I ended up with reading different text each time I was reading it. It was a few sentences and I thought I saw the letters move and make new words, eh. And even during the reading process it was rather hard to remember the sentences. Does the memory stands behind it? Is it hard for brain to make any text as still as any object I can see in a dream?