1. Debate in person requires reliance on memory while debate in text uses direct quotations.
2. In text, there is no pressure to respond within a given amount of time; one has as much or as little time as one needs to make a clear, well-supported response where any misunderstanding would be the fault of the listener, not the speaker.
3. In person, points have to be addressed serially which can easily cause relevance issues as one tries to raise other points while an initial point is being discussed. Text debates allow full, point-by-point responses where discussions on multiple points can happen at the same time and the separation between these points made clear. Long explanations also do not need to be cut off in the middle for further explanations — the explanation can be read in full, and then clarified.
4. There is no intimidating presence, making it impossible to shout someone down or otherwise bully them into silence. Even if multiple people gang up on a single person, that single person can respond to the multiple people in one post rather than having to shift between multiple related conversations with different people possibly asking wildly different questions.
5. Factual citations can be included in text for further research.
5a. On the Internet, this research can be done easily.
6. The lack of time constraints in text helps to prevent the use of rhetorical tricks, as one can step back and look at the argument again, or even go to someone else for a second perspective if they feel that the argument is ‘off’ (that is, it seems to make sense but has the echoes of an argument that in fact does not at all, or it seems to make sense but does not seem to make any valuable or relevant point, if any at all).
7. No one will complain about how loud you’re typing in a text debate, unless you’re at a library with really old keyboards.