I think that they recommend Caesar Milan says it all!
Avoid would be my advice!
It's not a good idea to let two dogs go at it, muzzled or not, and will only breed fear and further aggression. That said, I can't see where it has said that this should be tried, haven't read it all but am replying quickly whilst trying to compose a mega long email too! Sorry!
I wholeheartedly agree though that bringing the nervous/attacked dog into controlled contact with submissive dogs is a good step. (Here I go again... in the rescue I help out at the owner will often take a previously attacked or dog-aggressive dog out to meet his own, trained dogs (stooge dogs is his word for it!). Here he is in total control and he KNOWS his own dogs and knows that SIT and STAY mean just that to them. The troubled dog will both feel no threat and has total trust in the rescue owner.
However, it must be said that this man has been working with dogs for eons, and takes no crap! He can BELLOW! And sometimes that's needed. It doesn't work for every dog - the GSD I'm fostering from them (and they ain't getting back cos I love him!) is one who doesn't respond well to such an approach and will run. But, many, most even, will find an odd comfort in the bellow of someone they trust, knowing as a result that this person is in comfortably and capably charge and they don't need to react.
As for taking a stick with you to deal with an attack or assumed attack and saying "If they do not grab the stick and do not back away, begin poking the dog with the stick. They will soon grow tired of being jabbed and retreat.", it's a fecking recipe for disaster, for both dog and owner.
Poke an aggressive dog with a stick?????
WTF????
Sorry, booyhoo, but I wouldn't recommend this advice. I am NOT an authority on anything dog, I just go by experience and am not a trainer or behaviouralist as I'm sure you're aware (I have a GSD who sings and dances on a lead when he sees another dog or my other dogs/DC are ahead of him, trust me, it's a work in progress... or not progressing very fast, tbh!), but I am learning all the while and have taken on board the training and advice I see and am given by not only the dogs I know in rescue but by those who have put in huge amounts of time, trouble and research into training their pet dogs and I can only say that I'm 100% certain that none of these people would recommend letting 2 dogs "go at it" or use a stick as described.
The only deviation from this is the "spat" between dogs as opposed to fight, when sometimes, if the dogs are not going to come to harm, it works to let them grump and sort their own pecking order out, but that's a far cry from letting a dog be attacked by another.
Am madly busy for the next couple of days but am going to ask around as to what others with more experience than I would do in the event of a dog attacking another.
Will let you know what is said.
HTH