Yes, I am sure it is possible to do better, but that's exactly the point of such record attempts - creating a challenge for others who can then try beating it. So if there are eight or nine other freedivers in your club who can do as good breathing patterns as you, and you beat the record, I bet the current team won't take it as an offense
BTW, one breath each 6 minutes is really amazing. Did he tell what he was smoking? I wonder if we could get some real yogis to a freediving competition, to see where the limits are in comparable conditions.