Fighting back can enhance a relationship between D/s
if it's something both know the limitations of and have
established their own personal boundaries within the
relationship.

I've found knowing how far you go and what is or
isn't acceptable only comes through time shared
with that person.

How those boundaries are defined for each of us
comes a great deal from our personal life experiences
(our environment) as some here have already mentioned.

Sometimes both (or even one)
might need that little extra edge to things.
A way of releasing an accumulation of sexual energy that
being less forceful or demanding simply won't do at that
moment in time.

As in all things there's an element of risk involved but
hopefully we also try and maintain a sense of right and
wrong (a form of balance) and know how far is too far.

Sometimes you just crave a little wrestling, working
up a sweat as bodies glide against each other during
the tussle. Hair being pulled or twisted and wrists pinned
down as you either take or are taken.
A more animalistic role as beasts in the wild where it's
conquer/be conquered.

GULP-I'd best stop now and shift focus to something
a little more tame.