We have about 2,000 students using lti_grade_passback to Blackboard and another 2,000 not using LTI or grade pass back with v. 2.19 WeBWorK
Even though we have set $debug_lti_grade_passback = 0; I still see a lot of warnings in the webwork2.log like
[warn] submitting all grades for user: (student-ID)
[warn] lis_source_did is not available for user: (student-ID)
These are for students whose accounts are local, not from LTI and their grades are not linked to Blackboard.
Can I prevent these warnings for the courses not needing LTI by placing in the course.conf files and empty string for the LTI grades, like $LTI{v1p1}{grader} = ' ';