You asked for a thought , here's mine.
Backspace and offset are ENTIRELY different things, tho related. Youd
best keep your terms straight.
I can't be bothered to remember which way is + or - offset, so I don't try. And "offset" needs to be calculated, backspace can be measured. Tell me a wheel has such and such offset, I don't have any idea if it fits. Tell me the backspace I'll have a good idea if it fits or not.
Rant over.