Even when stomata are closed, water is still lost, especially through the waxy cuticle. Don’t stress your plants with too much dryness!
Climate change models assume a certain amount of water vapor, as water vapor is its own greenhouse gas. This could place current models of water vapor as low, suggesting that climate change may end up being worse than predicted.
I think I remember John Boyer at mizzu in the late 1980’s. He made crazy equipment to measure cell turgidly. He had the poor glass blower in chemistry make micro tubes. He gave a graduate seminar showing his devices. He was doing groundbreaking reasurch.