Rule side effect executes again.

In our setup I'm attempting to add the logged in users email address to the xEmail metadata field.   I have the following side effect set in the rule.

<$xEmail=getValueForSpecifiedUser(#local.dUser, "dEmail")$>

I'm leaving the field as an edit so that users can correct the email if it's wrong in ldap.   The issue is, after completing the check in, the value pulled from this idoc script is taking precedence over the value entered by the user.  I'm guessing that for some reason this is executing again, although I thought the side effects only executed on the loading of the check in screen.  Am I wrong on that?  Any ideas on how I can pull the email of the logged in user, but still allow them to update it if they want to?