I didnt yet really understand when it's profitable or wise to invest ur eth into dai and when to pay the dai back to get ur eth liquid again..
when u need some liquid stable coin to pay bills but dont wanna sell ur eth? in case it rises?
and if it rises the dai will cost less.. compared.. I guess that's the core idea..
I believe the only reason to do this is to save taxes.
If you wanted to leverage there would be better tools to go long or short i believe (like futures or simple margin trading)