When using website optimizer do I have to install this code from http://adwords.google.com/support/bin/answer.py?answer=93179&topic=10972 on our site? The reason I ask for is because our site is an affiliate site, so it leaves from our site and goes to the merchants site? We never had to use this for conversion tracking? I wasn't even actually aware of it? Do i have to use this with website optimizer?