Hard/Full Refresh of form on field change
A full refresh may be required in certain situations, such as making a tab visible (sections on a tab) visible based on a formula
Add the following to the field whose value is being changed
<xf:action ev:event="xforms-value-changed"
if="//SYS_COMMAND_PARAMETERS != 'OPEN_DOCUMENT'">
<xf:send submission="FIELD_VALUE_CHANGED"/>
</xf:action>