It does but that setup runs into limits on throughput of individual servers, and doesn't have the same drain/fill/failover capabilities discussed in the article.

To be clear, the HAProxy+vrrp+dns is often a better solution, but this describes an interesting design for a load balancing system that can handle many orders of magnitude more traffic and have maintenance without breaking established connections (one of it's core design features)

Imagine if you need a lot more than two HAProxies and they aren't in the same rack/subnet; that's where more sophisticated techniques come in.