Yeah, EFH for a backhand defensive slice with lots of spin, slow pace, low margin over the net, wierd skidded bounce. You've seen vids of Haas, and Fed's return on high wide backhands...those more conti side of EFH. You've seen Roddick and even Nadal using it for variety and keeping the ball low so the opponent doesn't groove into the higher bouncing normal topspin backhands.
Just gotta stay IN the shot, don't lean back, don't be tentative, full stroke and confident it will clear the net by 2' and go well deep, slow down drastically on the bounce, go sideways a little, and the deadball effect can cause many mishits from your opponent.
Conti grip slices are pretty normal, so most players can counter it easily.
EBH slices have more pace, but still sorta normal.
I haven't seen too many SWBH gripped slices lately, but some good ones were TomBrown and sometimes Roswall would go there on higher backhands. Those moved pretty fast and really skidded hard and offset.