Dolly is adorable! And she's got quite abit of color on her head for a deafie!
You could never eliminate white boxers complete, flashy is a big trend w/ boxers, and that leads to white puppies. Somewhere around 25% of boxers born will be white, and about 25% of those will be deaf. A responsible breeder will place them in good homes w/ a spay/neuter contract.
Although I disagree that they are any less healthy then their colored siblings. Other then a higher chance for sunburn (I don't consider deafness to be a health issue), but that should be true w/ any pink skinned dog. For example I own two great danes, a harlequin from a questionable breeder, and a well bred white, my harlequin has had his share of health issues, my white has been the picture of health. She has a great coat, and great skin (the harl has allergies), both can be sunburned, but it's not a problem unless we are going to be spended ALL day in the sun. Right now it's over 100 degrees and we just came in from spending a few hours out there. To my knowledge the only thing white boxers are more prone to would be deafness,sunburning, and possibly just more sensitive skin.
With double merles (which are completely preventable) they are prone to deafness, blindness, and more prone to seizures, but oddly the breed of dog seems to make a difference.