I held a mere SECRET security clearance last summer (not even TOP SECRET, which is what Clinton has) and I had to go through weeks and weeks of training, aside from many friends and relatives being interviewed. The consequences of using personal devices to send even just OUO (Official Use Only ---- not even classified) information was pounded into our brains. We were told countless stories of people getting their clearances revoked and being fired for using personal USB drives, let alone servers.
No matter how you spin it, Hillary is either the most incompetent government official in the US, or she intentionally broke the law. I would bet more than 99% of individuals who hold clearances would agree with me.