Dealing with player injuries when they are 'Questionable' to play

[Gradius]

I would like to know what the optimal solution is to determine what to do with a player that is questionable to play in a game. It isn't too hard to determine whether a player will play or won't play when listed as probable or doubtful, but I'm still not certain what to do when a player (an important one, mind you) is questionable. I have read that, Justin7, says to cut the player's rating in half, which makes some sense, though I'm not sure if this is optimal. Another strategy would be to not bother with the game.

Any opinions?