Not you but others...
I guess it also should have been clarified if we were referring to single player or multi, or both. Personally I haven't really played it single player so, what exactly does the delta difficulty do beyond make it harder?
My general thought was they tried to combine the tactical decisions of R6 with the vehicle/control point game play of BF2. IMO, it really mix that well.
Then again, I don't care for Bioshock either so maybe I'm just abnormal.