Ok it probably did not make that much difference in speed,, a little for sure
and I have read,, that as the arrow gets heavier, the tip weight is not making as much differnce in the speed,,dogwood shafts can be quite heavy, and maybe that was a factor,,
maybe with a sinew or rawhide string,, it was not an issue,,the few fps,,
and I have a feeling if an archer wanted a bit more cast,, probably just went up in draw weight a bit,or pulled the bow further,,, and the tips were more for durability and ease of stringing with rawhide or sinew,, ok thats my 2 cents,,