I had heard the let in-not let out instinct regarding Rhodesian Ridgebacks, but not Mastiffs, so that was fascinating. I do hope it is something I never have to test out, though.
Our Mastiffx went to the vet yesterday because I wasn't going to attempt trimming her toenails myself - they are so thick & strong (and blardy hurt! lol). The nurses took her out the back (first ever visit, btw) and she was apparently a very good girl <3 I've not seen even the hint of a grumpy bone in her body.
Pups .... sigh what more is there to say? They're pups! <3 <3 <3
I'd be a sucker for the fawn pup. :D