Are landing pages really more valuable than home pages?

According to Joshua Porter in his blog, Performable, the landing page is definitely more valuable than the home page, and by valuable you can infer you get more conversions from a landing page than from a home page. So many of the articles that discuss the ROI on landing pages versus the home page tell you how to increase the ROI (i.e., have more conversions) but not necessarily why this is the case.

1. Landing pages and forms are actual interaction points-the home page is a one-way communication point, you communicate with the user; a landing page and/or form is two-way, the user can communicate back to you. If you "listen" to the conversation you will be better informed on what your customers need/what and therefore can provide it.
2. Landing pages contain the information a customer needs to make the decision to do business with you, no matter what business you are in.
   
3. Landing pages contain very specific information for a very specific audience. The landing page provides the information necessary to close the deal after the customer has shown interest.
4. Home pages are a catch-all. The home page is the funnel that catches all incoming user traffic whether it is a new visitor, returning visitor, family and friends, and so forth. The home page has to be designed to appeal to all visitors and not be too specific to any one type of user. Home pages have to handle everything which is a totally different purpose than that of a landing page.
5. Home pages are often "political", meaning every department/unit of the business wants a significant piece of the home page. The thinking here is that because the home page gets the most traffic it must be the most important page of the web site. This is not true (re-read #1-#3 above). This leads to wasting time and money on the design of the home page when it offers little to no return on the investment.
   

Please do not misunderstand, the home page is an important part of the overall web site and therefore, time, money and energy has to be devoted to it. The home page should guide the visitor to other pages within the site, i.e., a landing page. But because the landing page serves to close the deal (i.e., conversion) where the home page does not, it makes sense to focus a majority of your design efforts here because you want to be profitable, no matter what business you are in.