Hehehehe... The only reason I asked was because I knew you couldn't resist one of your no-nonsense tutorials. I'm a baaaad boy!
Seriously, thanks for the tutorial. Ironically, I had discovered the thing about turning dynamesh on and off just a day or two ago completely by accident. If you want to use this on something you've already modeled on you can, but you have to make sure to crank up the dynamesh/resolution slider and turn on project(optional, but it does help maintain details). This is NOT a way to retopo your model, so keep that in mind. It just gives you more geometry to work with and it usually adds polys to your mesh, so be careful if your poly budget is running high already.