But the thing I’m not clear on.... which is harder, addition or subtraction? Could somebody please just tell me!
Similar to which is harder, multiplication or addition?
For one who has learned elementary math, they can probably multiply 2x2 as easily as they could add 2+2. They could do an exam of 100 questions of easy addition (3+4, 7+2...etc) as quickly as they could multiplication (4x8, 3x6).
However, for some multiplication will always feel harder than addition.
The same probably also applies to subtraction.
Someone even did a science project or two showing this!!!
Not that any of it should be a problem for those who were the game's intended audience, anymore than figuring out whether you had an attack of opportunity or not.
But, I do know several that never figured out how THAC0 worked (I was the DM normally, so the burden would fall on me anyways) and had gotten their university degrees!
(and the same also applies to attacks of opportunities, always was asked whether they or something else were going to get one).