Is there any value in generating emails with AlternateViews?

I have a page on my ASP.NET 3.5 website that uses code to generate an email. This code has been set up to exploit the AlternateView facilities of System.Net.Mail so that each email contains both a plain text body and an HTML body. I did it in this manner simply because it was described in an article I found. 
The HTML emails work fine but I am not aware of how I can test the plain text version. In fact, I'm not really sure whether there is much value in creating AlternateViews. Who exactly will benefit from the plain text body option? 
I would appreciate comments....
David 
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