Catalyst - 3:13 am on Dec 29, 2011 (gmt 0)
Well I don't think it's considered a rewrite or proxy.
Plus it would not be a matter of one domain looking like the other and there would be no dupe content. All the content is on petproducts.tld/dogs. dogs.tld is just an empty domain that forwards to petproducts.tld/dogs.
It's a very common and accepted practice many people do in other circumstances for other legit reasons. For instance sometimes if someone has a long ugly domain name, they'll reg a short one and send people the link to the short domain, which forwards to the long domain.
Or you set up a blog on blogger and forward your domain name there so instead of giving people a long link to blogspot whatever, you give them a link to yourdomain.tld
But anyway probably not a good idea. I'll just have to figure something else out.