You might look into using trigonometry to actually verify the edge angle, I wish I could tell you how but I'm a bit challenged for trig right now, lol.

How many times have the blades in question been sharpened? Reason I ask is it seems to take several sharpening to get rid of the bit of weakened metal at the apex from belt grinding the edges at factory.

I'd recommend removing the chips if at all possible and resharpening at the same angle and repeating just to see if it's happening consistently with similar chopping use.