Most no gi specialists don't enter gi comps. This is true. But I do think that many no gi specialists train in the gi. In fact I think most of the best ones do. There are very few high level no gi grapplers that either didn't train in the gi for a long time or don't do a pretty decent mix of both. I have posted a shit load about Gordon Ryan today but honestly he's one of the only ones that comes to mind. He and Dean Lister are the only guys I know of to win ADCC with such a small amount of gi training compared to their no gi training. Obviously there's Mark Kerr but he was a straight wrestler and not a jiu-jitsu guy. When I think of the my favorite no gi guys ever I think of Marcelo, Braulio, Galvao, Jacare, Rafa, Cobrinha, Gordon, Pena, Lovato Jr, Keenan, Tonon, Cooper, Glover, JT...most of these guys do/did both gi and no gi training. Jake Shields is probably the most successful jiu-jitsu guy that has done almost no training in the gi.