a lot of people free feed successfully... but imo it is much better to schedule meal times...
scheduled mealtimes help you to keep track of how much your dog is eating,it is important to know if there are any appetite changes because this is a sign of possible illness and sometimes it is your only sign...
it also makes it easier to know when to expect the dog to eliminate (go to the bathroom) this is extremely helpful with house training....
some dogs just cannot be free-fed bc they will over-eat, and free feeding has been know to contribute to bloat...
oh, and food is a very important tool in training your dog... you can use scheduled meal times to help train many behaviors...like waiting patiently...