Lu,
The only mistake I made in my post was regarding where the maximum rate of pitch change occurs. It is in the 30 degree arc either side of the neutral position - the reason the maximum rate of flapping happens at the position of maximum/minimum pitch is because the vertical movement of the pitch operating arms is at it's least 30 degrees either side of this position. This means that the blade spends 60 degrees of it's rotation at or near maximum pitch and 60 at or near minimum pitch. Angle of attack determines lift and therefore flapping so the max rate of flapping is still at max and min pitch positions.
Draw an accurate sine wave - the gradient of the slope is not constant (or it would be a straight line instead of a curve) at the top and bottom of the curve the gradient is least and at the point where the wave crosses the x axis, it is at it's steepest. Converting the rotary motion of the POA s to a vertical motion gives changing rates of pitch change per unit of angular displacement.
If you still don't believe me then get your trigonometry tables out and look at the difference between the sines of 0, 30, 60 and 90 degrees - the change is NOT LINEAR and therfore not constant.
Helisphere - I must go to work but I wil try to answer you question Re Lynx tonight.