Ok. So I just figured this out, but it's a hack solution. I'd like to see if anyone has a better solution as I may like to repeat something like this.
But here was my solution:
All I did was echo the csv string that I create (instead of return it) and then immediately call exit; right after the echo statement.
Isn't there still a "load headers" field when you define a Manager Action? I haven't looked lately.
If not, your solution might be the best, although I suppose you could create a protected resource with no template, write to its content field, and forward the user to it.
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