I just completed an internal launch and I didn't have the sales letter written until 2 days before the launch. When you go through a launch process the sales letter is not a critical element of the success. All the content you give before hand should do the selling.

However, now that I'm doing a big JV launch I have the sales letter but I don't promote it on my partner page. Maybe I should but I didn't think seeing a sales letter would clinch a deal for me.

-Nick