you are talking about something that has smiliar features like the blog-example-app by maidsafe aren’t you …? MaidSafe Dev Update - October 4, 2016 – TEST 10
or like the forum project decorum is creating (just to add another keyword you can look for)
so yes 100’% possible
sorry i don’t understand the question - where is the difference …?
if you share some data that data can be accessed by the people you shared it with. they can look at it inside safe, possibly store it in their safe account or can decide to make a local copy of it so they have access when being offline.
once you shared the data the other user has access to it. like a bitcoin wallet where you just shared the public key