I am experiencing some strange behavior with alerts in a specific instance I'm working in.
The subject line when the alert is sent is something completely different than the subject line in the email editor.
The alert is approved with no draft. The text version is a copy of the HTML version.
The alert is using a very simple template with one mkto-editable DIV and nothing else.
This is happening across multiple similar alerts, where the same unwanted subject line is over-riding the subject line as displayed in the email editor.
Very bizarre! 
Hopefully I'm missing something simple here. Anyone else experienced this?
Josh Hill thanks for the ideas.
I had gone through a similar check list yesterday, and at the end of the day I managed to fix it using a variation of 5.
It seems like all the emails that I cloned somehow retained elements from the original, even though these weren't visible in the editor.
By creating a brand new email with the same template and copy and pasting all the exact text and HTML into it -- all of a sudden everything worked as expected.
My hypothesis is that the cloned emails got corrupted somehow. I didn't feel like waiting until Monday to contact support so I just re-created 17 alert emails instead 
Nonetheless I saved the ones that weren't working to show support. Maybe there is a logical explanation but it feels like a bug of some kind.
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