OPTION_ALLOW_OVERRIDE value not considered or impactful

[crstauf]

The field accepts the allow_override parameter (set as value of OPTION_ALLOW_OVERRIDE class constant), but the set value does not impact the field settings or output value.

The default setting is true to enable overrides; setting to false appears to do nothing. A review of the code indicates that OPTION_ALLOW_OVERRIDE is not referenced anywhere other than declaration and default value.