I was fascinated to hear that good freedivers can equalize to something like 60m without mouthfill by just relaxing. Not sure how it is possible, but in the beginning when I dove to 28m I had nothing left to equalize, then after a couple months of frequent fun diving with some exhale practice I got to 31m yet still had plenty to equalize further. So is it true that once we get acclaimed to deep diving, RV of the lung can decrease and equalization can come on itsown ?