I think the GP was talking about what you might call "expressive range". Anything that can be expressed in a string of characters of a given length uses at most

I think the GP was talking about what you might call "expressive range". Anything that can be expressed in a string of characters of a given length uses at most the full expressive possibilities of that string. I think it's a silly point, because the meaning of lisper's comment was clearly that the added structure makes s-expressions more powerful than the Unix convention of "plain text". The Unix standard of lines within which there are fields delimited by some character is, itself, a very primitively constrained/structured form of text, so it too is less expressive than raw text could be. But this is a daft discussion.