Sketch objects can read/set areDimensionsShown and areProfilesShown but not if points are shown. I realize that these supported options are ones available when you right click on a sketch in the browser and that toggling point visibility is not one of these options but points are messy at times and I would like to have the option to present a cleaner sketch, esp. during previewing where the user cannot possibly turn off point visibility.
I agree and have wished for the same thing myself. This is a case where the API is dependent on what the sketch core supports and unfortunately it does not support turning off the point visibility. It's especially important for API created sketches because they tend to be more complex and it's usually not expected that the user would manually edit them.
Another approach to this is that in the future we hope to support the ability to group multiple features and the sketches and construction geometry they depend on into a single "custom feature" and you would have the ability to hide the dependencies so the user wouldn't be able to see or access the sketch but just see the final result body.
Bugger...
If not part of the sketch core how does the constraints panel control the display of points? Could there be a round-about way to get at this via constraints that isn't too embarrassing? 
And actually, this is mostly a problem with splines - they show the control points where nothing else shows all its points as such. Is it possible that this could be considered a bug in consistency and splines should not show their points when not editing a sketch 
?
I wasn't aware of the "Show Points" setting in the Sketch panel. That means that the core does support it and we should be able to expose through the API. I'll add it to our backlog.
