It is not a matter of rates (which makes the diving profile not linear) it is a matter of equilibrium between two forces. The tank, emptying, pushes you up. The suit, compressing, pushes you down according to depth. You can adapt depth, so you can keep the forces in almost perfect balance for at least great part of the dive, not just one moment...The rates won't be equal and won't offset.
You will still be exactly correctly weighted at only one moment, which is what this sidebar is about.
This was standard in the seventies, before BCD were in use. Most dives I did at that time were on steep slopes or vertical walls, so the depth was a free variable, which could be adjust searching for neutral buoyancy. And if the amount of weight was "proper", it was quite easy to find that equilibrium point.
Of course, if one is over weighted, being already negative at surface, going down one becomes even more negative, and the whole dive was dangerous and very fatiguing.
If instead one was missing, say, 1 kg of weight, it was not a big deal: instead of starting neutral at 10m, you are neutral at 15m, and from there you continue going down while the tank becomes lighter, keeping the two forces in equilibrium. It was easier to do than to explain, particularly to people who never dived without a BCD, nor can do a proper "capovolta" for winning the initial buoyancy in the first 5 meters.
These are lost arts....