Some of the DAL attributes are marked EDITable so that a provisioning
workflow can modify them (Entity Activity). On the other hand, we need to
display those attributes in the detail portlet/Edit mode, in a read-only

This does not seem possible.

Looking for a way to do that - Read only display in the Detail Portlet -
Edit Mode.

<side note>
As a workaround, I've tried to create another instance for such attribute
in the DAL, and did not mark 'Edit' on this one. So now I had: myAttr and
myAttr-ReadOnly. I included myAttr-ReadOnly attribute in the Detail portlet
prefs - for Edit mode, and left myAttr attribute in the View mode.

The strange thing is the Portlet shows a duplicate value in the View mode,
and No value for this attribute in the Edit mode.
</side note>