Normally if you change anything that effects the tune of your bow, you will have to change your sights to compensate for it. Especially if you are messing with your rest or nocking point. It changes the direction your arrow is pointing when it leaves the bow, so the arrow impacts in a different spot. I don't fine tune my sight until I am done tuning. I just shoot for groups and ignore where they actually impact in regards to where I aimed. When I get the groups I want, I set my sights to put the arrows where I want them.

Good luck,
Paul