I have a policy which requires clear written communication in advance for late payment plans and I penalize other behaviors (with fees).

I am not sure why Ned jumps immediately on any feed that has to do with PIP but again seems that BP allows this type of behavior here.

No matter how good you are at tenant screening (and by the way most PMs are not great), you cannot control - LIFE or its bad circumstances or tenant bad behavior.   

Possible amendments: tenant alone accepts all liability for any harm caused by pet; no vicious breeds allowed; tenant must get rid of pet at first indication of dangerous behavior (this one may have a downside--it makes it seem as though the landlord has ability to remove the pet, which is an inference to avoid since it increases the possibility of landlord liability generally).

No reason to modify behavior = no modified behavior.

I agree...we try to be forgiving with past mistakes but if it is behavior that has happened within the last 3-5 years I would say that is a pattern of behavior and there’s a strong chance that it will repeat with her rent check within a few months.

I try to be straight forward with my tenants leaving all emotion out of it and just give them a road map as to what the consequences are if the following behavior continues and that it is "out of my hands."

It is human psychology and behavior.

My manager has been charging a $250 flat non refundable pet fee, which seems sort of useless, in fact may even make a tenant feel like they've "paid in advance for any damage, so why be astute about animal's behavior?" 

But the reality may be that the middle men are making the most profit – even if not the most profit, the issue is that its an undisclosed amount of money ( hence smells like dishonest/ double dealing behavior).