Definitely will be trying the "Positive Interrupt".
Frank is middle aged, and has always been a yard barker, we just went on more walks and had less time in the yard.
This winter he wants to always be outside (could be the nice and warm woodstove being used a lot this year) and the barking is crazy with no response to any call - I did trick him with a lazer once.
He's crazy for food and balls so rewards won't be a problem
We'll try some low stimulus interrupting tonight!!