Correct, as usual. By limiting the concentration of the lead sulphate in solution you limit the possibility of crystalization. Equalization may fource some of the crystals back into solution, but once those crystals form they provide seeds for more crystals to grow. By coating the plates they reduce the batteries capacity by effectively making the surface area of the plates smaller.
This reduction in area will also accelerate plate wear-out by forcing the areas uncoated to provide more lead into solution, reducing plate integraty in that area.
Sometimes I wonder that it works at all.
There are two types of fools...
One says this is old, and therefore good..
The other says this is new, and therefore better...