Question on an Option in FA Book Controls -

Release 12:1.3

The Option - Disable Automatic Merge of Payables Source Lines, on the Accounting Rules Tab of Book controls form, when checked, should interface all the lines on an AP Invoice as different lines in FA MASS ADDITIONS with each line's status as NEW. but when it is checked it should Merge all the different lines on the AP Invoice as a single line with status as NEW and all the other lines as 'MERGE' is my understanding correct.?

I am seeing exactly the opposite when left unchecked in our system currently and am not sure of the reason. ( the option Allow unallocated line types is left un checked as well)