> And all that risk for what benefit? none of this processing will ever be faster than doing the processing in place.
The benefit comes into play when you mix data from different sources that don't trust each other (to the point where they would never agree to one of them doing the processing in place). Homomorphic encryption allows combining the data without ever revealing it to the one doing the computation.
For example when two parties are interested in making a deal, but don't want to reveal it unless the other party is interested as well. (The example is usually a date, but it could be applicable to voting or other situations where both privacy and unanimity are desired.)
By performing a homomorphically encrypted computation, they can set it up to only reveal the final decision, but not the individual inputs that determined it, so nobody loses face.
The benefit comes into play when you mix data from different sources that don't trust each other (to the point where they would never agree to one of them doing the processing in place). Homomorphic encryption allows combining the data without ever revealing it to the one doing the computation.