Point-and-Figure-box-size-decimal-places

With WL6 I can open a new chart window, set the chart style to Point and Figure chart, then set the Box Size to as many as 13 decimal places. However with WL7 I can only set this to 2 decimal places.

My code does 13 decimal places of accuracy in order to precisely set the column count to a desired number. Would it be possible to increase the WL7 box size resolution to 13 decimal places also?

Secondary, I have developed a wrapper/facade design pattern that enhances the point and figure class. Here I have a box size property but this defines the property type as a decimal instead of a double in order to avoid double precision multiplication inaccuracy. Currently I cast back to a double when setting the chart. However I wanted to raise the question of changing WL7 PointAndFigure class BoxSize from double to decimal. This no doubt has impacts that I am not aware of, and I can continue to cast, but I wanted to ask the question.
Thanks