I think you also have to consider that the manufacturers probably lower their prices as well once a model is nearing it's shelf life. Especially on drivers since new models come out at least annually. Versus iron sets that seem to hang around for 2 or more years.
For instance I recently purchased a TM R9 460 driver for $147 on Amazon.com
That was probably at or around what the box shops paid for them when they first came out. Hence the $300 price tag for us.
I assume that TaylorMade probably dropped their price on the R9's to around $99 or under to the dealers once the R11's started showing up.
Also, I have seen in my recent hybrid search that TaylorMade will release clubs to online dealers with an "ARP" stamp. Asset Recovery Plan, which, after researching stands for overstock they are selling or customer non-open item returns. They sell it cheap and in turn we benefit from the cheaper prices. As long as you are willing to forgo the warranty from TaylorMade. However most online retailers will provide you with a warranty on the club.