This might be a totally dumb question.... but i'm just here learning so no one be mean lol..
I am wondering can you place an elevator or rudder on the leading edge of a stab instead of how it's commonly done connected to the trailing edge of the stab. I've seen some aircraft like this.. or what i thought was this .. like the russian Sukhoi i think it's the SU-27 forward swept wing aircraft. But maybe those were spoilers and not alierons on the front.

Is there anything to be gained or lost on an aircraft by putting elevators or rudders sweeping off the leading edge of their respective tail surfaces. Also what about Alierons on the leading edge. Or does just not make any kind of practical sense??

PA