We've evolved a 128-line server into 20 lines of mostly unique code. At each step along the way we've been able to focus more on the task at hand instead of on infrastructure necessary to write servers.
Each step mimicked the various stages of POE's development. All the tedious parts still exist, and all the higher-level conveniences are built using them. As a result, if a program needs more control than a high-level class provides, it's straightforward to write something on a lower level that does precisely what is needed.
Code on the low- and high levels continues to multitask and network because all levels boil down to the same common denominator.