title: angular 2 Do we need avoid two way databind when not necessary?
body: <p>I search a lot to understand if there is some bad performance if I use two way databind (ng-model) all times at my forms instead of one way databind.
  I know that with angular 1 for each two way databind a new watch is created and with huge applications with angular 1 we can have performance issues because this. Now I need to know if with angular 2 this does make some difference if I only use one way databind or not?
  Two way databind need to be avoid when not necessary?</p>