why does a JDE sales order entry creates a new OD purchase order when adding a new line for an exist

I know this issue has been reported before but ORACLE replied with works as designed.

Issue description if add a new direct ship order (SD) with 3 lines, it would create one purchase order (OD). Now if I go and revise the existing SD order and add a new line with the same supplier and requested date, instead of adding the line to the existing purchase order, it would create a new OD purchase order.

My question is: Why is ORACLE not resolving this issue by adding the line to the same OD purchase order when it has the same supplier and Branch? Is there a risk? is this a high impact change? What is the impact? Thanks!