Screen Update Statement Is Executed Without An Error

I ran into a screen update problem in a project I was working on and couldn't find a solution, so I wrote some test code in a new workbook as follows;


Sub Flkr()
'-------------------------
'Screen update test
'-------------------------
'Select sheet1
Sheets("Sheet1").Select
'Disable screen update
Application.ScreenUpdating = False
'Select sheet2
Sheets("Sheet2").Select
'display message
MsgBox "Why is the %&$@ screen updating?", vbCritical, "??????"
End Sub
Seems simple enough,eh?

When I step through this code the first statement works(sheet1 is selected)
The next statement is executed without an error, so I assume it works
The next statement sheet2 is selected, and the screen updates!