IMO it doesn't matter if they line up with your fletching but it seems to help me if I put them all on the same. I'v got one bow I shoot with a release & broadheads fly closer to field points for me if I put them on with one blade right on top. My other bow I shoot with fingers & install them with a blade straight out on the left side to get clearence from the riser. Thats with 3 blade heads, If your using 2 or 4 blades I think it would still pay to put them all on the same.