as coined in the Ruby Rogues podcat #168 with Craig Muth of Xiki fame :
DAVID: That is awesome. So, you talked about you started this 12, 14 years ago, tinkering with stuff, just on the side. Something would distract you and you’d go after it. And I’m just so happy to realize that there’s a fine line between yak-shaving and ADDDD, which is ADD-driven development.
[Laughter]
DAVID: And that line…
CRAIG: Never heard of it.
DAVID: Is 12 years.
[Laughter]
DAVID: I have hope that 12 years from now, I will have a cool product as the result…
JAMES: [Laughs]
DAVID: Of what I’ve been calling yak-shaving but I’m now going to call ADDDD from now on.
(all credit to David Brady )
Definition ADDDD : when your yak shaving metastasizes from procrastination to shipping code (or, at least in 2014, posted on GitHub)
Note : my knowledge of this technique is purely theoretically because I use the more pure YSDD.