Some observations: Riley growls at Thor much more frequently at night, almost exclusively at night. Riley's growling/guarding may start at quite a distance which is surprising to me. However in discussing this with my obedience teacher, this can happen. Riley's resources include me, treats, and space. Also, there may be a growl instanteously (fraction of a second) followed by a smile which puzzles me. If anyone has any ideas on this let me know.
Some positive observations: The boys love playing with each other. And they play hard. They greet me in the morning in a tight space, both very happy, no signs of resource guarding. Riley seems much better at sharing space.
I think that the training is working.
My gut feeling is that I will need a combination of management and more training ala Coren.