Although, the sheer volume of conversation that you have in a LDR is much more comprehensive than if you are together.
I mean, if you have a 3 hour convo on the phone of a saturday afternoon with your GF who's on the other side of the world . . . you actually talk for 3 hours.
Most couples who are together don't actually do that. We get sidetracked, distracted, or occupied with other things.
We go to the cinema together, then to a concert, all the time being performed to, we converse shallowly for 20 mins to end the evening, followed by ... boink,
OR,
We talk, non-stop for 3 hours, ... as we know each other longer and deeper, the convo gets more heart to heart . . .
I think that actually LDR's (long distance relationships) are more strong and stable, in terms of knowing the other person, than close-by relationships!