A really weird argument. One school of BJJ claims grappling in our Jiu jitsu gis is the best way to learn to grapple well. The other school of though says that training in the gi only makes you better at fighting in a gi, if you are going to be grappling without it, or fighting in real life/mma, you need to train without it.
So who is on who’s side. Plenty. Most of the Gracies feel the gi is uber important. Eddie Bravo, and who knows how many MMA Jiu Jitsu guys would argue the other way around. It really doesn’t prove anything to go down a list of fighters and tell you what they feel on the subject, there are nearly endless names on both sides. Let me instead lay out why the average grappler feels on way or another.
The Gi guy likes the gi, because it gives him a real advantage on wrestlers who wonder into class. Sure, double leg me, but with these handles we forced you to wear I can coke you out or at least control you. The No gi guy likes the fact that once he gets all sweaty and slick, holding on to him is really hard. There’s no controlling me. I’ll flail until one of us lands in a submission. People who are less flexible prefer gis, people who are less technical prefer no gi. Yeah, ticked both sides off with that one. I don’t mean everyone!
Once you reach a higher skill level it starts to come down to this, people who have rank in BJJ like wearing a gi, because it goes with their belt so well, heh, makes them look like the boss. People who have bounced around from school to school might be highly skilled, but would never stay in one place long enough for an instructor to tie a belt around their waist, these people hate the gi because it reminds them that they don’t have the rank to wrap around it. Most of the time when you see a school that says “submission grappling” but doesn’t state a style, that’s him.
Personally? I like some of both. I like to roll in a gi against no gi opponents. I always tell them, “Please, use it against me as much as you can, its good for me.” You have to be willing to work outside your comfort zones, and if you have ever rolled for a few hours in an un air conditioned gym wearing a gi, you will be out of your comfort zone. So I guess I’ll go with the very safe answer of “Just train more.”