It is simple if you play it simple, having reasonable TTLs and expectations around it (i.e. well behaved resolvers and caches should take up to TTL time to consider to refresh the record after a change, and you should not worry about badly behaved ones). But you should understand what goes below, or else things you don't expect may happen.
Anyway, DNS is far more than direct resolution, the article didn't scratched reverse resolution, DNSSEC, views, setting secondary servers or other things that may go deeply wrong in different ways.