Well, when 5.5 first came out, it was kind of OK, but now it's almost noticeably worse. It can be done, but requires a lot of effort, just more and more round, and actually, the Gemini Pro on the web (which should be 3.1 Pro) is actually doing a more stable job.

The thing that I ask it to do is like take X and Y paper into Z paragraph --- a not-so-silly model should think of how information in X and Y are related and how they support the whole article to synthesize this sentence in a way that is coherent to the article, but 5.5 now will just copy the stuff without any reasoning about the relation. Of course, this will cost a lot of tokens and will be obvious if not done. One clear indicator is that in a few rounds you can see the length of the article get bloated to 2-3x undesirably long, which is clearly because it is not analyzing/synthesizing the info.