I'll admit that I didn't entirely get this the first time I saw it. Marcelo has been known as an advocate of "jiu-jitsu" as the best conditioning program for jiu-jitsu. But I'm not sure if his approach has been properly appreciated. As with all things Marcelo, a brief example makes the point clear.
I will add that this is something that Prof Carlos has been talking about more and more recently in asides before or after class. Maybe it has something to do with his focus in advance of the Pan Ams (coming up in just a few weeks!), or something broader about the approach to training he wants to pursue.
In either event, for those of us who have only so much time devote to anything not revenue-generating, Marcelo's point about training intensity is worth keeping in mind.