Just a matter of getting used to, I guess.
So while they often get overly-full of markup like these ones, the markup follows a pattern that's rarely broken, and it becomes very easy to follow after you've gotten through a few threads.
For both, it seems like I read messages in random order and then have to guess at the general gist. There's seems like no easy way to get an accurate timeline of things.
I think the problem is made worse when people forward (or retweet) as part of a conversation. There's often forwards of other email chains included as a reply with or without unique new messages being added.
Sometimes people are left off part of the CC chain for some messages, so there are gaps in the flow.
The problem is compounded when there are multiple email threads about the same thing, often because someone replied to an old version that turned into a new conversation. Or they read just the first sentence in the original email and replied about that in the newest follow-up in a 100 email chain.
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As an off topic side note, text chat programs are the ultimate form of communication. It has the fewest flaws of all mediums. It's linear in a single timeline that everybody has (and has the history to). It's pretty hard to mess up the history of what happened or who said what.
I enjoy it when people get frustrated about text chat. It's almost always because they can't dominate the conversation by talking over people or "win by talking loudest" which makes them frustrated and uncomfortable.
I don't use Twitter so I don't know what it does, but if you look at the email, the oldest posts are quoted first, so you just read the message top to bottom like anything else.
And if that's too confusing, there are links to every message in the thread at the bottom.
If you're talking about the quoting, the ">" marks denote one level of quoting, so the more ">" marks in a line, the older the message. As long no unwashed heathen has top-posted their reply, then you can just read the message top to bottom in chronological order.
From top to bottom, like we did for centuries.
Replies at the top are the devil’s work. Or maybe Microsoft.