I've read that I should use email subaddressing when registering for web sites. For example, if my email address is [email protected], then, when registering for somesite.com, I should use the email address [email protected].
How effective is this at controlling annoying emails from somesite.com (or, in the extreme, outright spam)? What is to prevent somesite.com from stripping the +somesite tag and sending directly to [email protected]? Is email subaddressing something that I should bother to use, or are the benefits limited?