If you know that your dog will go for another dog , whether or not he has yet to actually bite , then imo he should never be let off the lead and should be muzzled if taken where other dogs go , just incase he gets away from you.
what you describe can be traumatic for a nervous dog to go through ... and could turn the nervous dog aggressive towards other dogs itself through fear of being attacked again

sorry hun , I know you love dogs and are a great owner but thats how I feel

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