Suppose two people are updating info about a T shirt: size=M color=green Suppose Al is in charge of color and Betty is in charge of size. They both get th

Suppose two people are updating info about a T shirt: size=M color=green Suppose Al is in charge of color and Betty is in charge of size. They both get the form at the same time. Al sends oldsize=M newsize=M oldcolor=green newcolor=blue Betty sends oldsize=M newsize=S oldcolor=green newcolor=green The server ignores Al's oldsize/newsize and Betty's oldcolor/newcolor because the values are unchanged. You end up with size=S and color=blue no matter who sends the update first. By "faking it" I refer to the fact that the old values are user-supplied data. Validation of the new data is a separate issue. Someone could "fake" an old value. This merely means they would change a value that they were already authorized to change. Messing with the "old" values on the client side has no hack value. That's why I'm not at all concerned about it.