I have heard of this doctrine as being 'fire insurance'. They want to live all of their lives for the devil, and at the very last moment get right with God. That does not work.
I was very glad to hear of a man who followed through on his committment to live for God if he would be raised up. I have heard of too many stories of people who made that vow, and then failed to follow up.
The
Acts 2 experience is the only way to go. If there is any mercy for those that do not find it, God has not revealed that in His word. There is no man who is without excuse for failing to be saved. More than 2/3 of the world no who Jesus is, and He will make a way for the truly hungry to hear the entire truth before they die.