What is the purpose of the "Sheet1, Sheet2..." tabs in SolidWorks Drawing data card

I can understand (I think) what the " @ " tab, "default" tab and any additional configuration specific tabs are in a SolidWorks Part or Assembly data card.  But, in the SolidWorks Drawing Data Card, it seems to only utilize data contained in the " @ " tab.  I had assumed the "Sheet1, Sheet2..." tabs were similar to the configuration specific tabs in the Part or Assembly data cards in that you could have values in fields on the "Sheet1" tab that were different than values in fields on the "Sheet2" tab.  However, it seems in the Drawing data card, only the values set in the " @ " tab apply and populate all sheets of our drawing's title block.  If this is the case, what is the purpose of those "Sheet1, Sheet2..." tabs?

What brought this to my attention was that we have our part and assembly data cards automatically set the same properties in our drawing data card.  The update occurs automatically when we change a value in the part or assembly card, but it only updated the drawing data card's " @ " tab.  It left the old data in "Sheet1, Sheet2" tabs.

Thank you,

Dave

SolidworksSolidworks Pdm enterprise Pdm