Hi Guys, I'm a newbie here (so be gentle with me)
I'm training my 3rd dobermann now, so in terms of dobe's...I have a little experience
My first dobe was an 18mth old rescue dog who would piss himself at anything unexpected or new....by the time he was 3yrs, he would confidently face anything (including jumping into neighbours cars if they left the door open...he loved going for rides
My 2nd Dobe "Daims" unfortunately passed away this morning at almost 11 years of age...he was bought from good breeders at 6mths and was alway an outgoing, energetic dog, but with the mildest temperment you could imagine. he could handle crowd situations, children sitting on his head (don't ask!!) and wouldn't give so much as a growl...but when he was "working" anyone who came near was treated to several snarling warning barks, then silence...if a threat was at hand he would instantly take protective mode, stepping between me & the threat, and would never start a fight, but if bad manners were displayed by others (dogs & humans) he would quickly finish it.
2 weeks ago I adopted another dobe from the RSPCA...he's had little or no training, showed strong drive, but unpredictable due to anxiety. whereas I could call Daims off at anytime, unless I was actually being attacked, Zillah the 15mth old PC (problem child :D) hasn't learned his lesson yet, and isn't backing off on command...still it's only been 2 weeks.
I suppose what I'm trying to say is that Daims was a dobe with good nerves....he was always alert..but would ascess everything with a high degree of intelligence, if it was actually a threat..he was ready for action...if it wasn't, then he'd just ignore it.
Zillah at the moment is (although he has strong drive) actually showing weaker nerves because he isn't ascessing threats appropriately yet. he's improving every day though, with alot of training, love & encouragement, and is responding really well considering his background.
I worked in the security industry for 15 years (although never worked my dogs for that purpose) however, I did train them to be quite capable of doing the job if I ever decided to go ahead with it.
BTW, I did train & worked my horse in security.
From my experience, nurture has a far more profound effect on a dogs nerves, than nature....however nature will have alot to do with temperment. Both can be manipulated/trained by positive & negative handling
...just my 2 cents worth (hope no-one minds me butting in )
cheers
Di