Personally do not allow marking or stalking while leashed, and believe that barking should be quieted on command.
Have you tried desensitizing and positive reinforcement with said equipment? My dog used to run for the hills with the vacuum, now he'll play with it, all I did was ignore him (and shut the door
) I would think that you certainly do not want a dead dog that responds with ears back and tail down, I have seen these dogs in class and they are just not enjoying it, while my dog is go-go-go and happy to listen and focus. That is not to say corrections should not be delivered, but as was mentioned, I correct only and rarely when there is a choice, during formal training, and when the dog knows it is wrong - breaking a known stay duration/distance, not sitting, breaking focus, etc. If the dog is clearly not comfortable, end what you are doing and do something fun, why push it?