That's semantics -- it basically means you cannot fall because God will not let you. And the non-elect, again by God's will, fall and are damned.
I don't see it as semantics, it is an improvement over "once saved always saved". It means that once someone says the sinner's prayer that he is not free to go back to the same sinful life that he came from. And, he is not free to be "faithful" for a while and then turn away permanently. If the salvation was true, then the person will not fall away permanently because God promises not to let that happen.
Semantics is saying that God wills people into hell. God is not the author of evil, and hell was not built for people! God allows some people to to not accept Him and they wind up in hell by their own choosing. With our sin nature at birth, that is what would happen to all of us, but that God spares some and causes His elect to come home, by installing saving grace and faith to some.
How can you do anything on your own when you deny free will? Whether you fall or not fall is God's will according to your belief, so it is wholly irrelevant and indeed meaningless to even speak in terms of what you can or cannot do -- for it is obvious that Protestants believe that man cannot do anything on his own; in other words a captive robot used for one or the other end.
I say that I do no good on my own. But sin, this I do (as a saved person) on my own. Whether or not we are ultimately saved is all God's will because we believe that the Book of Life is already written and God doesn't use erasers. :) We do not experience being "robots" because we do not see the future. But, God already knows every good and evil that we have ever done or will ever do. He causes us to do the good, and allows us to do some evil (sometimes to teach), but it is all already sealed as to whether it will happen.
As a believer, and comparing myself before and after, I know for certain that there is a mountain of "extra" evil that I would have done were it not for God's active presence in my life. I also know that since becoming a believer that a lot of "good" has happened that wouldn't have occurred to me to do as a non-believer. This is "some" evidence of a regenerated and saved heart, at least to me. :)