It does not always, but this is the theory
show your D, then when 49ers run the
routes DBs read where the receivers
are going--and then they know who
their guy is.

They react and hopefully get there
and break up the pass.

If they do their job--they can slow
even a good offense

again--don't love it, but we have to get it
it ain't changin'--at least don't think so but
never say never