My thoughts? Well, here goes, with a grain of salt.
I think dog aggressive canines can do well in a beginner group class setting under the proper instruction. Though I do believe that they should be privately assessed first for the level and type of aggression that they are displaying. Fear aggression needs to be handled somewhat differently than pure aggression, prey aggression etc.
If the levels are high, they should be worked in a private class first, one on one with the instructor, encouraging desensitization, and only then progress to the group class environment. If the levels are low to medium, sure, let 'em in. They can then learn how to behave appropriately around other canines with a positive, but firm approach. Of course, the handlers level of experience, knowledge and comfort definitely comes into play. If the handler can not control the dog in a proper fashion as directed by the instructor, or is not comfortable handling their dog around others, well, back to privates for them.
On the other hand, I do not believe that human aggressive canines should be in a beginner group class setting and here's why.
Too many people, including instructors, do not know how to appropriately deal with a human aggressive canine. There is a huge liability to the instructor/school if the dog happens to break free of it's owner and go after another student, and of course this means there is a huge safety issue for the rest of the students in the class. The other students are probably not be well versed in how to avoid a confrontation with a human aggressive dog. The "flooding" of people in this situation can cause more agitation and frustrate the dog further, causing it to retain it's aggressive view to people. And, of course, situations play out differently if it is fear aggression, or pure aggression.
In human aggressive canines, it is more common to see fear aggression towards people rather then true aggression, and private instruction on desensitization is very necessary. These dogs can be a huge liability and must be managed correctly in order for them to live safely and comfortably around people. I will not delve into details on how to desensitize here, but it is my opinion that these dogs do not benefit from a group class setting in beginner training or being flooded with people who have no idea how to react around this kind of canine.
In all my years around dogs, dog sports and training classes, I've seen only one truly human aggressive dog, actively displaying some fear aggression but becoming more confident in the situation, though the dog looked to be badly trained in some sort of personal protection venue. It's reactivity was quite high, especially around women, which is an oddity in itself because fearful dogs on the whole, normally display stronger reactions (be it fight or flight) to men rather than woman. And the fact that it looked to be well over 90 pounds didn't add any positivity to the situation.
Not by my choice, this story hasn't ended yet, but I'm curious to see the outcome, so we shall see if I come away with all of my limbs intact in the end.
Handle with care...
EDITED Nov. 25, 2009 - Whew, said dog has been removed from class to work one-on-one with the trainer (what I was hoping to see). I'm not afraid of dogs, not even nervous around aggressive ones, but I'm glad to know that my limbs will be kept intact for later use.
