That’s not the same thing. For a red dot we are talking about hitting the same target point if the dot is on target regardless of what portion of the window you’re using.
The analogy for an iron is that you’d have to correct your offset for the notch misalignment.
To illustrate:
These red dot utilizations would yield the same hit.
To get an iron to do the same
That’s why dot window size matters.
I did some iron notch rangefinding and notch offset is obviously specific to rear notch / front sight width and slide length.
With a thin front blade, misalignment can be significant.
This is me shooting pairs with the front post in different places in the notch.