Is There a Better Way: Updating the same row within a Transaction

Question

I have a stored procedure that runs the inputs through a series of validation queries, and kicks out a parameter detailing if record will be saved with "complete" or "incomplete" information. Then, we start a transaction, save the data to a couple of tables, commit. Done. Essentially this:

EXEC dbo.ValidationProcedure --(sets output params)
BEGIN TRANSACTION
MERGE TABLE A (uses output params)
MERGE TABLE B
COMMIT TRANSACTION

In addition to this, we have a view that has the same validation queries, written such that it returns all occurrences of invalid data within our tables; the queries in the procedure version merely check the inputs provided (both the validation procedure and view look at data for both TABLE A AND B). This view returns the exact error code, message, recordID, etc. and we use it audit queries, to get error messages on displaying the input form, yada yada yada....

My issue is that we have the same logic in multiple places, which I hate. My question, and potential solution to this, would it be bad practice/poor design, to remove the validation procedure all together, and do the following:

BEGIN TRANSACTION
MERGE TABLE A
MERGE TABLE B
IF EXISTS (SELECT * FROM ValidationView T WHERE T.ID = @ID)
BEGIN
    UPDATE TABLE A SET Incomplete = 1 WHERE [ID] = @ID;
END
COMMIT TRANSACTION

I thought of doing it this way a while ago, but, I was not fond of affecting the same row twice. It seemed wasteful, unnecessary, and an incorrect way to go about it; I'm hoping I am wrong about this thinking. But now, I'm having second thoughts and would like to know if we can unload some code overhead by going with the second example, or should we keep the course and maintain both the validation procedure and validation view.