It depends in what you bind them to and the methods you use. Nothing, a lot of things, good, bad, who can say? I suggest being a little more specific. Bindings can be used for so many things you might not think of.
Onthe downside you could drive them off if the do not desire it. If it is outside their normal character people will sometimes sense and reject the change. Otherwise it could potentially drive them to be closer than you desire. If you do it make sure you are clear on your intentions