This discussion got slightly offf topic, that might have confused you about what signature exchange really is. Here is how the real signature exchange works:
In your forum for example, you do not need to promote your site via your signature, so if you and I were to have a signature exchange you will have my forum signature in your posts say in your forum, that way all your post have a link to ukwebmasterworld.com as part of the signature.
I will do the same for you, I will have lifesupporter.com signature on my profile so that all my post advertise your forum. Not a brilliant explanation but you get the gist
Its a bit like link exchange where you put a link to my site from your site and I put a link to your site from my site. Its just that we are exchanging forum signature in signature exchange.
Temi