A little bit behind on this one, but the second segment I recorded for the 3D Printing Today podcast. Episode 43 if you want to listen to it at the 28 minute mark.
Decimating meshes is now part of my workflow, especially if the thing I've been making involves sculpting with dynamic topology. I do it quite a lot. And for the most part I can keep the effect of the reduction to a minimal so that the final print is doesn't look decimated, assuming you don't scale up your print. While other tools have decimation tools, I do mine in Blender because... well, I do almost everything in Blender.
Of course, if you want to learn more I cover decimation in 3D Printing Blueprints Chapter 7. And, here's an idea. If you would like to learn what I teach in 3D printing blueprints, but aren't sure you want a copy for yourself, ask your local library if they have a copy and ask them to get it. That way everyone in your community can benefit from my big 3D printed brain.