[Sharlin]

IME, often the text is gibberish, or at least nonsense semantically, and/or changes as you move your eyes, especially if you look away for a moment. The same applies to eg. clocks. Details never seem to be very stable in the dream world.

[modzu]

i've found that to be the case for anything (not just text) in normal dreams; but one of the most surprising characteristics of lucid dreaming ive experienced is the stability -- for example in one dream i looked at a persian rug up close and could see the different colored fibres of the fabric. that said, things can certainly change dramatically and rapidly (...and now im flying!)