Well it hasnt been in the excess of 2 years since he first got it fixed has it... im pretty sure a sword that size is meant ti take a beating.... hell even his old sword that he killed 100 men with didnt break then... so im sure the D.S has alot of "life" left.
Most broadsword are really strong when striking with the edge, and thus only take a good sharpening to get a lot better. But when you strike on the flat side of the sword its an other story... (kinda like katana if you want, but it can be applied to most swords) And when you look at what grunbeld did... It must certainly have weaken DS blade and god (Miura) only know what will happen...