I have friends who actually think their husbands are totally clueless and it pained me to witness their treatment of these men when they wanted to do something, whether it was just change a diaper or take the kid out to the store.
Now, granted, I would worry a bit when my own husband would 'take them off my hands', because we had different approaches, ie; when they were toddlers, I used wrist 'leashes', he refused to. But he's not stupid and certainly not incompetent. He didn't like it the first time I was going away and, in fact, had me take the kids with me, but that was more a situation of scheduling than anything-he was unwilling to change his work schedule to send the kids to school or be there when they got home.
But, incompetence knows no gender and neither does nurturing.
One friend of the spouse's was a volunteer fireman. Wife was at work or somewhere and his Plectron went off. He forgot about their newborn sleeping upstairs and ran out of the house....there's your 'incompetent dad' story..best I could do.