To be honest, if someone ASKS me with the labratwat (and provided he's not been tasked to do something) I will say yes, because he knows. If he's mid job or off lead then you get yelled at. My other dog is daft as
duck but because of the breed etc there is a no touchy rule.
And sometimes if subjects are scared of dogs it smoothes things over if they can pet the dog first. It won't stop the dog doing its job though


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Sitting isn't a +ve indication per se (depending on how they are trained).. It's the dog deferring to their handler. You work with them every day and you know their body language when they are working.
The best part is having: Hundeführer on my jacket/car as the English tourists instantly have a stroke