Having custom merge tags at the workflow level makes it super easy to change information across emails.

For instance. If I have a webinar template I like to use for follow up emails, having global merge tags for that workflow would make it super easy to update emails across that entire workflow with date, time, topic, etc.

Currently, If I need to change details for a webinar it would require going through each emails in that workflow and update them each manually rather than have to go into each email individually I can simply set the global tag and it changes it in each email as needed.