I don't use CR's to give out XP, only to judge the power of a craeture, and since I don't follow the wealth guidelines too closely, not even often at that.
I don't care about how much xp a classed minotaur should give, or what classes it should have. I develop an adventure, and give out xp when it is finished. Doesn't matter if the PCs won or lost, if the slaughtered the foes or outhought them. For that there are in-game rewards like fame and fortune. XP will accumulate no matter the luck or skill of the players, and at a rate set by the DM and the group.