And yes that fitting tolerance accuracy only comes into play during particular kinds of calculations that use a kind of refinement process to create their result, like Surface/Surface intersection is one of the main ones.

But for things like entering in coordinates where you're drawing lines and arcs the fitting tolerance does not apply to anything in that case.


So I mean yes definitely the changeability aspect of the constraint systems that MCAD programs offer is definitely useful for editing.

But you should be aware that a fitting tolerance is used in all other NURBS based CAD programs as well - that's not something that's just unique to MoI. If you've assumed that only MoI uses a fitting tolerance and other CAD programs just magically use infinite precision on all operations, that's not correct at all...

- Michael