I've learned the hard way that many charts are off, i.e., they recommend shafts that aren't stiff enough.
And I have had the opposite experience. What it comes down to is finding the right amount of deflection on an arrow for your particular bow. I like to keep my bow in tune with the proper arrow insofar as keeping the arrow passing as close to center shot as possible. Anything more then about 1/8 inch left of centershot is too much. I don't like to get right of centershot. This is with a compound, right handed, with release aid.