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That's an interesting question. I quite like the weird discipline of being forced to organize material into bite-sized chunks. But for developing an extended argument it would of course be hopeless.
A way in which Twitter is good for this is that (a) as Tim says, it forces you to organize material into natural bite-size chunks; & then (b) it enables threaded commentary at the chunk level. Apart from in-person conversation, I believe it's the only medium to succeed at that
