Hi Burr, well the problem is that in this case the amount that things are off was by 0.0000000000001 units, it's so small that it's quite hard to see it. Just seeing that extrude behaves differently isn't really a great diagnostic tool itself, it would be better to later on have more specific diagnostic tools that were focused on doing actual analysis.... Rather than just a mode for making operations fail I mean like I guess is basically what you're asking for?

- Michael