Before you get confused, let us just explain what distinguishes the back to back position from the independent sleeping position. The independent doesn't involve any touching, whereas the back to back means your backs or butts still have physical contact with each other while you sleep. This one is kind of cute - you can still touch each other, but still have that freedom of your own space on the mattress.
Unless it's a particularly hot and sweaty night, we don't see why you would stop doing the back to back - it's comfortable and it's affectionate. In our minds, there's no real downside to it. Having said that, we don't think it necessarily says anything that positive about a relationship either. It's one of the more neutral sleeping positions for couples. Almost like the Switzerland of sleeping positions.