I've seen that video, I think it's WAY too time consuming! I don't know what others do, but the first few tutus I made were sewn. Basically they were just tied tutus but I sewed a layer underneath the elastic to make them more secure. I don't do that anymore.
The stitch was loose & long, so it didn't pull or snap, even when the elastic was stretched. I never had a problem with it & never received any negative feedback. But now I don't see the point. The tied tutus I've made since are equally secure & it's one less step!
Oh, I've done 1 other kind of tutu that was sewn that maybe is more of what you're talking about. Instead of tying, you have two layers of tulle (in strips, just like the tied tutus) one on top of & one underneath the elastic. Bunch it up & sew. It is really full looking & doesn't seem quite as bulky as some of the tied tutus, but the fullness is more down than out - if that makes sense.