When creating a custom class for an element an inline style block is added to the header of the page and .myclass.bricksclass{} selectors are used.
Reusing the custom class on another page creates an inline style block on that page too.
Ideally custom classes should be added to an external style sheet when that box is checked (they are not) and ideally the selector should be element agnostic, e.g. .myclass{} is enough.
Same but different:
As it stands extra page weight is created by the use of custom classes styled in the editor, and on every page that they are used.
Yeah I know, it’s the extra targeting I don’t like though. (along with no external style sheet)
Plus there could be confusion since “brickselmentclass” is named for the type of element it is used on even if the custom class you created is designed to be use on different elements.