He's not saying that you _should_ install conda within a virtualenv, but that some have tried with some success. At the end, one of his conclusions is: "If you

He's not saying that you _should_ install conda within a virtualenv, but that some have tried with some success. At the end, one of his conclusions is: "If you want to install Python packages within an Isolated environment, pip+virtualenv and conda+conda-env are mostly interchangeable". So don't change if you don't have to. But he does give reasons why conda may be superior to virtualenv -- managing different version of Python, tracking non-Python dependencies, true isolation of environments, etc.