OK this is my brain on knapping
Pic 1 Shows how to isolate the platform (nipple)
Lower side approx 130 degree angle. Pressure flakes
where needed to isolate (front and/or back)
Make sure the nipple is wider if you want to make the
flake wider and stout enough to carry it as far as you want it to go.
The power in my experience is just like any blow necessary
to remove a large flake. More knappers need to knap larger
flakes. Just make suitable platforms.
Pic 2 end view
Pic 3 side view
BTW I wrap points over 3.5 inches long.