I wouldn't be so sure about the bad client behavior.  I've corresponded with providers in the past that have used multiple names.   If I had received communication from the provider you are speaking about, I probably would have thought nothing of it and just assumed it was a former alias.

There is a setting in Yahoo mail where one can control the "header" information.  

And not in a good way. Google always wants to link my hobby gmail to my REAL college email and I have to ALWAYS ALWAYS ALWAYS click no! I am afraid they may link it by themselves one day! I don't use gmail for anything but voice, and don't want google+ profile or other social networking benefits from google..... Never really gave any time to Yahoo but sounds just as bad!!  

Posted By: breadmaker

Was corresponding with a provider this week.  
   
 Her hobby address was  hobbyname (at)yahoo.com.  
 Her return correspondence to me came back as REAL NAME  caret [email protected] caret  
   
 Apparently, this was a defaulted name insertion because she had another yahoo acct under her real name.  
   
 She was horrified when I pointed this out to her.  
 No one else had.    (bad client behavior!!)  
 She has changed to another email service.  
   
 

You have to be very careful with what information you put down when signing up for an email account that you will be use for hobbying or escorting and not be logged into sites using an account with your real identity in the same session as when you are logged into an account with your hobby/escort identity.

agree completely.  Google is probably the worst by far but this is something to watch all the time.  Limit the real info and don't feel shy about not providing it.

A very good combination, IMHO.  
Encrypted email to and from fellow Hushmail users, and private browsing on Firefox. Also, set your computer to delete your browsing history when you close the browser.