I tried to "save as" an 11MB pdf file, then unchecking the option "preserve photoshop editing capabilities", but it only went down to 10.6MB. And yes flattening will only rasterize text and make it unreadable when being read. So I ended up using an external source. http://compress.smallpdf.com/ That link helped me bring down the 11MB file to 3MB quickly. But, I still do hope there's away of doing it without the need to go online.
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