The policies were different when policy saving was enabled by default. Left side of freedom had a policy cost reducer. Players would save their policies to grab this one as soon as freedom would open up, particularly for culture wins. Firaxis didn't like this playstyle, banned policy saving, and then later changed the freedom tree anyways.
I don't see any game breaking ways to use policy saving anymore, and I think it should be default again, unless someone can give a good OPed example.
Promotion saving, however IMO, is and has always been game breaking.