I have recently become more or less submissive to the rules of this site - well. to one of them, that is bringing the extended discussions from comments to chats. However, it is really inconvenient for me because in chat I can't write long passages - only few lines at each tie. It is so tiresome when I have to cut my answer to pieces and then to send each piece one by one. Why not increase the number of the lines that can be sent at one time in chat?
Chat is a conversation, not a blog, and not a lecture auditorium. If you are writing paragraph after paragraph before submitting it, then frankly you're not using it for chat. For the record, it does support much longer inputs than Caleb suggests, but that is intended (as you have indirectly discovered) for pasting things from other sources - and for precisely that reason, the markdown processing no longer applies in that case, as it is not assumed that an arbitrary paste from an external location will be markdown.
Here's my advice: put together a cogent sentence or two; press ret; repeat. This solves multiple problems:
- the "problem" you describe will go away entirely
- the other participant(s) can read the message as it comes together, rather than facing a sudden wall-of-text; and if necessary, can (as happens in real conversation) interject for clarification etc as necessary
- if something goes sour, you lose only 1 sentence, not a thesis
First of all, the chat text input field holds nearly as much text input at a time as the comment system on posts. Comments max out at 600 chars, individual chat messages at 500.
Secondly, the purpose is for dialog. We strongly discourage dialog type interaction on the main site in favor of structure question and answers. On chat the opposite is true. Large amounts of structure data is discouraged in favor of interactive communication.
If you do want to write a lot of content, there is nothing to stop you from just hitting enter and continuing on in the next message.
The chat does have one great feature that you won't find in most chat systems on the internet, and that is threading. All messages can be marked as threaded replies to previous messages, making complex discussions easier to follow.
If you use the tools for what they were designed for, they work great. If you try to bludgeon some other concept into them, they will be restrictive and you will loose all the advantages.
The best thing to do with the whole StackExchange suite of tools (sites, their meta's and chats) is to figure out what they do best, then use them only for that. Don't try to use them for everything. They aren't good for everything. There are other places on the internet for other types of interaction. SE doesn't try to fill the same niche as forums, bulletin boards, or other formats.