Comment by WillAdams

The thing is, the problematic curves often violate the rules put forward as best practices:

- place nodes at extrema (top/bottom, left/right)

- place nodes at points of inflection (middle of an _S_ curve)

- where possible/appropriate observe the "rule of 30" and place off-curve nodes not quote one-third of the way towards the other on-curve node

If one expected (or enforced) those rules, does the problem/math become easier?