ummmmmm FFA isn't supposed to be fair, it's supposed to be survival of the fittest.
I don't think raven put in the saber challenge to let people have "fair" fights during FFA, it's just a way to still be able to saber against one other person, 1 on 1, without others interrupting, and may the best saberist win.
if you're on an FFA server, you must know that some people are going to have more health, different force powers, more shields, or maybe even a force powerup.
if you suspect someone of having a decisive advantage over you in a duel, don't accept the saber challenge. if you do accept it, then do your best to win, use every move available to you as it's needed, and may the best saberist win. Or, if that doesn't appeal to you, go and get extra health/sheilds/bacta cannisters yourself and level the playing field.
the only place I know of where fights are supposed to be fair, is on duel servers, that's why you start out with the same health, same shields etc... when you respawn, those fights are designed to have each opponent start off with the exact same health and sheilds and force powers, and no interruptions from other players.
FFA is just that, it's a free for all, anything goes (barring cheating of course) and may the most talented or most creative player win.
the purple one