50/50 Sometimes damsels go crazy on a particular coral. I think this behavior is apparent close to breeding time. If you are concerned keep only one and keep in mind they change color dramatically as well.
I have had 4-5 species of damsels breed in my tank over the years and haven't had any actually eat live tissue from a coral. They have eaten dead tissue RTNing from SPS etc... also they have moved smaller corals if not attached strongly enough as well as break some smaller branches off around a nest site....and yes they are even more aggrssive when breeding or protecting a nest.