Good points Ron, happy that turned out all right for you and your Aunt too.
My statement about balance had to do with when one is already being physically attacked and has already lost control of ma ai, timing etc.
From my experience (and this is all I can quote from) many folks who are not sure how to maintain balance while launching a counter attack, or in response to something like a tackle, are unable to set their posture in a manner to deal with the attack and keep their footing, tend to be taken to the ground.
I guess it is something I see because it is something we specifically train to avoid. Often when engaged we can put ourself off balance by how we respond to an attack and therefore make it easier to being taken to the ground where, unless we have a single attacker and some grappling skills, desperate tactics tend to be used as the situation becomes increasingly desperate for us.
Your first point about letting someone bigger set up a successful tackle is right on the money. In the event that the tackle does come however, it is important to maintain dynamic balance (i.e. while moving and dealing with the attack) to ensure that one does not end up on the pavement.
Great points all around.