Hm. That's not a theory that's ever occurred to me, because I can sympathize with setting up a server because your employer's IT department sucks, and that's a simpler hypothesis. For instance, if she really wanted to hide her wrongdoings, why not get a state.gov email account for most stuff, and use clintonemail.com for the sketchy stuff? Or why not just have conversations about the sketchy stuff over the phone? Every entry-level employee at a private-sector company that says they're monitoring email knows exactly how to have an off-the-record conversation if they need to. You can't tell me the United States Secretary of State, whose job literally involves the most secret things in the world, doesn't know how to have a private conversation.

There's also the fact that she kept using her BlackBerry in 2008 despite being warned that even the NSA couldn't solve the security issues (which were about unauthorized parties breaking in, not about emails escaping government record). That's consistent with her wanting devices that were convenient and worked, and pretty inconsistent with her wanting to keep emails away from government archiving: she invited the cooperation of the NSA in solving her problem (until they said they couldn't), which she wouldn't want to do if the purpose of her using the BlackBerry was to hide emails.

So - when you say "odds are", what's the evidence that causes you to favor that more complex hypothesis?

The fact that no one in the history of the US government has gone as far to cover up their tracks.

What do you mean by "gone as far as to cover up their tracks"? That's attributing motivation, which is the entire discussion at hand; what action are you referring to?

If you mean that she used a private email server, remember that Hillary Clinton was the first secretary of state to live in the era where real-time email was a thing the average (American, at least) person had. iPhone and Android both came out in 2007; Hillary became Secretary of State in 2009. We have no information was to whether Condoleezza Rice would have wanted to, say, use the Dropbox mobile app had her job continued past 2009; that app didn't exist during her tenure. No one in the history of the US government had gone as far as to use reliable email on their mobile device to get their job done, but that's because Hillary happened to be Secretary of State during the years when real-time email in your pocket became practical.

Eh.... The extent that Chicago's mayor's office has gone to prevent me from getting their phone records comes pretty damn close.. I seriously, seriously doubt there are only a few situations like these.