Pretty sure that bathing advice (and the vinegar rinse) comes from a notable poster on "another doberman webforum" with something like 60 years of show dogs including a fawn with reputed good skin health...
Not disputing yours, of course. I'm very interested in what knowledgeable dobe owners have to say, especially those who have bred them and raised multiple litters (am I correct in recollecting that about you
@GennyB?
I agree there are a lot of factors at play- your water quality, ghe shampoo used, even the way you scrub- one poster somewhere I read (reddit? Fakebook? DCF or the other dobe forum?) made a common sense observation that rubbing vigourously against the grain tends to break hairs off? T/f?
So whatever I offer up here I am happy to say is only based on my dobe noob experience: 130 years ago that was so easy a keeper I've forgotten and the current BYB Bonnie NA/EU in pretty good health thanks to doing a LOT of homework here and elsewhere reading the archived wisdom going back 20 years- a gold mine of dobe owner wisdom...

thanks
@JanS
I especially value advice learned here at DCF as it comes from a different group of folks with a practical handson and down to earttn point of view, (if its ok for me to make that generalization?)
So remedies are like training advice-
Imho, try what works for the dog in front of you, including what vet says, whats out there online...the breeder, the dobe experienced vet tech, etc. and most especially the owners of dogs like yours...dilutes are not easy keepers, I understand.
I used to talk to everyone in the horse biz when daughter was in hunter-jumper, and learned something new everyday BSing in my broken spanish with the guy mucking stalls, pestering every trainer I met with dumb questions, the judges, horse acupuncturists you name it.... - and thanks to doing so with a brilliant farrier I'd cultivated just out of curiousity ...
saved us $thousands dodging a bullet on a purchase on a doped up horse because I asked for his advice...
boy howdy was the trainer pi$$ed that "we didnt buy that horse from her friend Penny"... got rid of that trainer later btw but that's another story...
Thanks for the reply! I appreciate you!