@matigo No, much longer than that, 4-5 years I reckon. I like it, and it does work well for me. The thing I don't do enough of is going back to see how my estimates of time required work out, especially when I am busy. So then it turns more into timeboxing. But I still find it useful to avoid interruptions and distractions.
This reply, you'll note, is coming about 25 minutes after that post. And, alas, I underestimated, so no coffee yet.
// @streakmachine