Geometric quality is easy to consider in terms of using trig and measured angles to solve for an (roughly) equilateral triangle vs a triangle with a very small

Geometric quality is easy to consider in terms of using trig and measured angles to solve for an (roughly) equilateral triangle vs a triangle with a very small measured internal angle. Also, it's easier to understand variables vs uknowns of GPS if you consider that direct measurement is of velocity and/or acceleration, and position is the resultant derivative, after taking into account the probabilities of various solutions. (Velocity and acceleration can be measured directly without making as many assumptions about various starting conditions.)