It's not strictly true. Minor, avoidable breakdowns of audiovisual isomorphism are possible. "Minor" means they're unlikely to confuse humans, though they may confuse stupid computer programs. "Avoidable" means you can speak and write so that the breakdowns do not occur.
- The Book (chapter 19 section 10) mentions that zoi quotation is an example of breakdown. A guard word that can safely delimit text may not be safe in speech, and vice versa.
- Some people may write both to and vei as "(", leading to ambiguity in whether the parenthesis is the start of a parethetical comment or a mathematical expression. The same obviously goes for the right parenthesis. (But writing this way is not common practice.)
- this is avoidable... by using to and vei. obviously things can start to breakdown if you don't follow the rules. it doesn't really seem worth mentioning, certainly not as evidence that there are breakdowns in lojban's audiovisual isomorphism
- Since not all pauses are written, even when mandatory spoken, that is a breakdown.
- Lojban Description text does not mark for stress. An unambiguous orthography (which is what we have, stress-wise) is not the same as an isomorphic one.
- I don't think that's a breakdown; similarly to pauses, the information represented by stress in speech is usually represented as word breaks in writing. I don't see any information gained or lost either way, though it's true the system is complicated and it's hard to be completely sure. See WordResolutionAlgorithm. mi'e jezrax
Others? Do any serious or non-avoidable breakdowns exist?