I've got a question, but first I've got to lay out what I'm trying to accomplish so the why is evident.

I've got my blog, and my affiliate store. I get traffic to my blog with SEO. My affiliate store is 100% dupe content, would be near impossible to rank -- I have no interest in promoting the affiliate store or wasting PR or backlinks to it.

On the other hand, my store converts people way better than the blog. And the orders are usually 10 times more money spent when people see all the options the store offers (as opposed to the blog which is focusing on one product at a time).

So ... I want to get people off my blog and onto the store within 1 click of entering my website ... for the best conversions and larger sales.

My method to accomplish this -- I want to cloak via http_referer. So if a page loads, and there is a http_referer ... and that http_referer happens to be the domain of my blog, it means someone is clicking from one page of my blog to another page. Under this circumstance I'll redirect the browser to the store.

This saves all my PR, all my link juice, all my relevancy etc from backlinks retained on my blog, because there are no links anywhere to my affiliate store.

That is my goal. I know how to code it no problem. My question is this: does anyone think Google sends http_referer headers to websites, and if it does ... would it send http_referer headers that represent the site it's browsing? I don't see why they would, but if they did I can see it totally screwing up my site because it would see every page is redirected to the duplicate content store. Anyone know the answer without me having to conduct tests ahead of time?

Googlebot generally doesn't send any referrers. You can check for yourself by looking for the Gbot entries in your log files. Google isn't really "surfing" your site; they strip the links out of each page and then fetch them in whatever order they see fit, so it's a bit different from someone clicking from page to page, where it is appropriate to send a referrer header.

I would combine your referrer cloaking with some other form(s) of cloaking eg. cloaking for the Googlebot user agent and IP delivery. You can the lists of Google IP block allocations from ARIN if you don't want to fork out for a paid IP list. Err on the side of caution so you don't fuck up your blog - better to lose a few clicks than to get banned.

Bear in mind that conversions will drop if you force a redirect on people when they are clicking and expecting to see something else (although you might still make more money than you're making just with ads on the blog).