Pulled my first chamber job in 8 months last Tuesday and the difference in my air use was wild
I mostly do pier and hull work out of Gulfport so I stay shallow, but last Tuesday I got sent down to 70 feet on a chamber job and my consumption went from about 90 psi surface to needing almost double. What changed over those 8 months was I got lazy and stopped doing my full pre-dive breath-up routine on shallow days, and it caught up to me hard at depth. The tender on my line said my breathing was way too fast at the start and I burned through my reserve in what felt like 15 minutes. Anyone else notice their air habits fall apart on shallow work and then bite them on the deeper jobs?
Same thing happens with stretching before lifting. Skip it for a month on light days and you don't notice, then you go heavy and your hamstrings remind you real quick. The body just stops doing the boring prep work when it thinks it can get away with it. Shallow dives train you to breathe lazy because there's no penalty. Then 70 feet hands you the bill. It's not really about the air, it's about the habits you let slide when nothing was forcing you to keep them.