Who knows factory cylinder heads ?

At this point, being they are not adjustable. Does it really matter ? Ha ha. I understand your point. But, nothing matters if they are not adjustable. So, why even bother setting the cam at any particular position or not ? That’s another reason, why I chose not to worry about cam position.
You do not see guys going all the way down the line adjusting hydraulic lifters with adjustable rockers just going down the line because they're hydraulic. They must be adjusted on the base circle PERIOD...