But, yes! There can be poor and super duplicated content.
I think that search engines do recognize when content it too "duplicated" and simply posying the same post over and over again is like keyword stuffing in the metatags.
Again, it is logical.
If you design a search engine, you will want results to be the highest possible quality, so you will put in place strategies to filter poor content.
I am prety sure, that for search engine developers, it is VERY easy to spot poor or overaly duplictaed content.
So, they simply won't rank these results high which is again LOGICAL!
They don't want to deliver poor content to their market.
So, the answer is to maintain the line of adding quality to the posts by diversifying the content as I said earlier with articles, videos, audios, etc + Adding as much value as possible.
SEO effectiveness works with quality content!
You have to think both of serving search engines + the real audience of visitors! ABSOLUTELY!