I agree with Matt that the best way is to cook breast separate from everything else, and there are a lot of ways to do that. Jasper White has a lacquered (sp?) duck recipe that is good.
re duck breasts, it often helps to pour out some of the rendered fat as it starts to build up in the pan.
If you're really adverse to duck fat, then I don't think there's any way to saute to get rid of it all without overcooking the breast. That is, the primary concern should be how the meat itself is done, then how the skin is crisp (which isn't hard to do), and lastly how much fat is rendered. (i.e., keep the priorities straight) You really can only render so much. Besides you can either eat the fat or just remove it with knife and fork.
There are techniques (I forget the fancy french name for it) in which you remove the skin and fat while raw, then vacuum pack the breast meat, and then cook it very gently in the vacuum packing. The meat exudes juices while cooking and reabsobs while resting in the packing. If you like to cook, I'd recommend checking into these.