I had 200-dives in and still burned through air a lot quicker than I liked. I improved quite a bit since Dive #1, but not quite there. A local course director told me that I should take his basic freediving class and he guaranteed improvement within the first session. I thought that he was full of it but the classes were cheap enough and I liked the guy (plus the cute babes in the class helped).
Lo and behold, he didn't give me a fib. My air consumption went way down after the first freediving session. It is nearly halved now (I'm somewhere in the high 200s or low 300s dive counts right now), than when I was doing my 200th dive.
Freediving training gives you two things that truly help with air consumption: 1) breathing technique that allows you to relax yourself - almost like Yoga or Zen but not quite, and 2) hellacious confidence in yourself underwater. I thought that I was a pretty confident diver by the 200th dive, but after you freedive down to 20-ft, put on your snorkel/mask, fins, and weightbelts WHILE wearing a 7mm wetsuit...I can see why those freedivers are like fishies in the water now.
Before the freediving, I know that with one breath I can do an ESA or CESA from practically any depth. Yeah, yeah, I practiced and all that with a closed valve on the tank. But now I KNOW that I can survive with one breath underwater. That takes my worries away and allows me to relax even more.
Freediving is the best kept secret in SCUBA training.