Joe,
If you don't use the force option of the tableupdate your first form will return a .F. for the TableUpdate and the error will be Update Conflict. This because;
form 1 makes cahnes to the buffer but has the other feilds buffered with their old vlaues
form 2 chane wsone of the other fields
form 1 does a tableupdate with the force option os it overwrites form 2's changes with what it has in its buffer.