[rachelbythebay]

People who know how DNS really works don't need to know that it doesn't really "propagate" in the conventional sense.

People who don't know how DNS works (and don't care) can be given it as a useful abstraction. If you have worked in tech support with people who want things to work and quite rightly don't want to know how the sausage is made, this might be ideal.

With anything, it depends on the audience.