[King Custard]

Ideally you wouldn't adjust your sight very far atall...if atall.
If you adjust your sight so that it is no longer 'above the arrow'...or with the side of the aperture on bow center- then you are no longer shooting through the center of the bow... the further you move the aperture away from the correct point- the worse the problem becomes, the less effective the bow becomes...and the worse flight and score due to haphazzard releases or form.

It's far better to adjust spring tension to get the differently spined arrows to each group in the center. (This is assuming of course that you don't intend to bareshaft tune both sets of arrows- obviously you cant tune a bow fully/perfectly to shoot two sets of different spined arrows this way)