Hi Chad,

We agree this is an issue.

There are several ways to improve the code here  to remove any potential problems when working with large numbers of added individuals, and to ensure optimal performance. Ive brought this to the attention of our dev team and I've raised a Support Desk ticket  (ref: 5218) on behalf of your Totara Partner. 

I think it would be worth considering using an Audience to add the users to the Certification - just add them to the Audience instead - or use a ruleset and a dynamic audience, this could avoid any problems hen the number of users becomes even larger.

We will keep you & your Partner informed of our progress in resolving this issue once we have a better understand of all the factors involved - thanks for spotting and reporting!

regards,

George.