MHMama,

I will not take any dog to a dog park to run unleashed &
interact with other dogs I don't know personally.Even then,
I think we run a risk. Pack behavior is not predictable and
we run a risk of injury to our own dogs , or other peoples's
dogs.
Walking our dogs on leash anywhere ,allows more
time for bonding & enjoying each others company. We can
learn a lot about our dogs & they can learn a lot about us
by experiencing a walk outside together. As you can tell I'm
not a great fan of "Dog Parks".

P.S. Maybe the guy meant his dog was only aggressive
with bigger dogs? I would'nt want to "guess" what he
meant.