I am not at all sure this is benign. The NSA stuff tells them where to look, but it's much nicer to get stuff thru normal investigative channels, then it can be entered into evidence more easily. Personal emails are not presumptively classified, whereas NSA intercepts would be top secret or above classified.
See how hard Nunes had to work to get some stuff unredacted in the findings today about Flynn (top article on Zerohedge). He already knew that stuff long ago, but he couldn't release it while it was classified.