This was caused because a small part of sculpt's radial control code did not make it into the new version. The old code would set a new object-space size by scaling it proportional to how much the new screen-space size was changed.
The solution I implement here is to do the same scaling inside the RNA callbacks. This way, users of those properties do not have to worry about inconsistency.
I added a comment warning that brush_set_size, brush_set_unified_size, brush_unprojected_radius, and brush_set_unprojected_radius do not guarantee consistency because it is not always possible to precisely know what the new unprojected radius is in all contexts where you might set the size.
I would implement the consistency check at the lower level (in those listed functions) but at this time I think it needs to be looked at to make sure that won't cause problems. In addition, I am not sure that scaling by the ratio of change is strictly correct in all cases.
In any case, this at least fixes the immediate problem.
Jason Wilkins
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