SSRS "Synch Dataset" vs manually adding fields to RDL

Epicor ERP 10
1

The “Synch Dataset” seems to break built-in SSRS reports.

Manually editing the RDL dataset’s query (as per the Epicor online help topic “Developing a Modified Version of an Epicor Shipped SSRS Report”) works.

Is there any time when “Synch Dataset” is required - or actually works?

2

BAQ Reports

3

So only use “Synch Dataset” on BAQ Reports.
Manually update RDL dataset query expression (after updating new RDD), on built-ins?