Our dog also has a bladder of steel. We rarely do it, but can leave her for 10 or 11 hours if needed. Feeding her is much more of an issue than letting her out. Quite often, even if we're home all day she only goes out twice a day. I find it kind of amusing because when I take her out for a mid-day walk she pees every 4 feet, but if I try to just put her out for a quick potty break she has no interest, or apparently need.