K.P.
C.,
I might suggest trying a supportive tactic rather than a harsh one. Perhaps at this point now she has become really uptight about going to the bathroom since she is being punished for accidents- and she is getting worked up inside about it. My daughter loves to help clean so she would have loved to clean the bathroom with me, too- it would have been fun mommy time just the two of us. I think you may be overestimating hersense of rationalization- as is she doesn't mind wetting herself becasue she doesn't mind the consequences. I really would suggest taking a soft approach. Ask her why she can't make it to the bathroom, ask her how you can help her make it in time, reward her for positive behavior (just like many people use sticker charts for potty training- you could give her stickers for each day she doesn't have an accident). DOn't make it negative and she might not feel bad about it.
Good luck,
K.