Wait For All
              ------------
                   |
  [DocType1]------>|
                   |
  [DocType2]------>|
                   |----->{PostProcessing}
  [DocType3]------>|
                   |
 {UserResuest}---->|
                   |

CREATE TABLE PreProcessingLog
(
	CustomerID			int,
	CompletionType		int,
	--Types are 1=UserRequest, 2=DocType1, 4=DocType2, 8=DocType3
	Primary Key Clustered (CustomerID, CompletionType)
)

IF (
	SELECT SUM(CompletionType)
	FROM PreProcessingLog
	WHERE CustomerID = @RecvdCustID
	) <> 15
BEGIN
	COMMIT TRANSACTION
	RETURN 0
END