The question https://english.stackexchange.com/questions/140857/break-down-break-out was apparently posted by a spammer, and will be deleted. Is it worth rescuing? I could answer it, but I would like at least a second opinion on it's worth. If you think it would go better at ELL, let me know that too.
There is no limit to questions of the form "which of these two prepositions goes best after xxx?", a fact the spammer knows and plays on. Though superficially interesting, it isn't something that we here can explain better than a grammar book, and (equally important in fact, though less so in theory) answering this one would soon flood the site with similar questions.
The question whether it would be welcome on ELL can only be answered on ELL.