If your new and old arrows are the same length, I don't see how the new ones could be 45 gr heavier unless you also added weight somewhere else. Even for two full length shafts (usually 30-32", which would be much longer than necessary for your draw length) going from 9.1 to 9.9 gpi would only yield around a 25 gr increase (all else equal). If the new arrows are longer than the old, then yes, 45 gr heavier is quite possible. Did you change anything else about the new arrows besides shaft stiffness/density?
Even if your new arrows truly are 45 gr heavier than the old, it's believable to me that your POI change might not be noticeable at short to medium ranges. How far out did you shoot? What size were your groups? Also, by what percentage did you increase total arrow weight? A 45 gr increase would be significantly greater percentage-wise for an IBO weight arrow than for a heavy hunting arrow, and I'd expect POI shift to scale more closely with relative (rather than absolute) weight increase.
Another possible contributing factor could be differences in shaft diameter. From the specs you gave, I'm guessing that your old arrows were 5mm Axis (9.0 gpi and 0.264" OD for 400 spine per Easton's
website) and your new arrows are Kinetic Kaos (9.9 gpi and 0.272" for 340 spine per GT's
website). The new arrow's larger diameter will slightly alter the launch angle, causing it to start its flight pointing slightly more upward than the old arrow (same effect as shifting the rest slightly higher). The diameter difference is only 0.008" and I don't know if that would actually cause any appreciable difference in trajectory, but it might be a contributing factor.
