He may be completely trustworthy with an able handler around other dogs though yes around biting dogs you can still see some anxiety there.
Still this is a great proofer to see how what they've established will hold up under intense and unusual circumstances.
I agree I would use a little different timing and pressure but like you write there's more than one way to skin a chicken!
E-Dog - 2012 WPBTCA National Championships
The time when screech owls and Bandogges howl and spirits walk and ghosts break up their graves.
Act I, Scene IV of William Shakespeare's "King Henry VI"