It's not about being rational or not, it's about discipline (or perhaps about ADHD for some people). I can fall for many temptations, but when I want something done (either as a hobby, or at work), I have no problems concentrating on what I need to be doing. And having extra screen space often helps.
Depending on the task, of course - there are times when all I need is one 80x25 terminal, and then there are times when having several as large as possible windows open side by side helps a lot, e.g. when analyzing logs from several cluster nodes.
I love the Wilde quote, by the way, I don't think I've seen this one before. :)