why a Worksheet Change Event during a macro

I am working on a phenomenal workbook created by a former employee. There are 20+sheets used to hold constants and collected data. There is a summary sheet to display it all.

He has a Private Sub Workbook_SheetChange(ByVal Sh As Object, ByVal Target As Range) that is active while the mega macro is running. Consequently when you step through it take far longer than it should. (I put a break at the end of the Workbook_SheetChange so I could F5 every time it ran but it's still a pain.

(1) is there ANY benefit to having a Workbook_SheetChange event firing while a macro runs?

(2) if I add an Application.EnableEvents = False then turn back on at the end could I cause other problems?

If the macro is take a long time and runs on every data entry it is probably doing a lot of data validation.

I can't post the code it belongs to my employer. I'm going to disable events and see what happens.

This workbooks is actually a template. All it does it takes user entries and calculate a cost. Then they save as for reference.

Thanks