Very good topic, there have been several nodes concerned with speed this weekend.

I'll add that, if you must rework code for speed, Devel::DProf is available to generate data on where you are spending your time.

That is not to say you should write inefficient code. It is worthwhile to develop the habit and skill of writing code which only does what it must. You can obtain overall speedier code that way without the expense of reworking, or the frustration of optimizing the wrong thing. I hope dws's colleagues were simply taking the opportunity to exercise some of those skills.

After Compline,
Zaxo