It will be a nice enhancement and it will also make Microsoft Dynamics CRM 2011 flexible, if I can modify read-only field in a workflow.
Let's say I have a field "Country" which is a lookup on a custom entity "Movie". The "Country" field is read only. I create a workflow on this entity "Movie". The workflow executes on any random field change. Now I add a step in the workflow to update the "Movie" record. When I go to "Set Properties" of the update record step, in the workflow, I can't select value in "Country". The reason being that "Country" field is read only on the "Movie" form.
I think we should be able to update fields in a workflow despite being read only. Read only is a UI property and update is a business requirement.
There are 2 workarounds: 1) Instead on making "Country" field read only through field property on form, make it read only through JScript. 2) Make this field not-readonly. Then create the step in workflow. Update the "Country" field in the workflow step. Change "Country" back to read only in the "Movie" form.
If an enhancement can be made to update read only fields in a workflow without going through extra steps of the workaround. This will save time in development.