Well, your world view is not reality. First, I have talked to people both in person and online and in person (Including a Pastor at his church) who admit that they can sin like the devil and still be saved; Second, there are testimonies of ex-OSAS propronents who felt trapped or enslaved to their sin because of the teaching of OSAS.
Ex-OSAS Proponent Testimonies.
Third, pure logic and deductive reasoning should tell you that if there is no real consequence to breaking a certain Law or Laws that truly matters, that is exactly what people are going to do. In other words, if people feel they will not get into trouble with the Law all that bad for breaking certain Laws, they will break them. For example: Take the speed limit Law on the highway. If the punishment for breaking the speed limit even just by a little on highways was spending time in jail for 2-3 weeks with heavy fines, what do you think will start to happen? More people would start to obey that Law better. Why? Because the punishment is more severe. The consequences are grave for them. Even certain non-believers do not fornicate because they know they could get sexual disease and or embarrassment by their family and friends. It is in realizing the consequence of their actions that deters them in doing what is good. In OSAS, you can sin and still be saved. You have taken away any real consequence that would matter to them. So what do you think they are going to do? They are going to sin, thinking they are saved. Maybe not everybody in the OSAS camp, but there are a good number who do so (Whether you are aware of it or not).