All that makes for interesting reading and I searched a bit more on the topic of viewstate and seo. While I appreciate the suggestion this is not something I want to integrate into mojoPortal at this time.
- I really do not believe it affects SEO at all, I feel confident that google is smart enough to ignore hidden fields. There is no evidence at all that it does have any impact on SEO and only speculation that this solution that moves it to the bottom is beneficial.
- Most of these articles are very old.
- There are indications in some that things break under a load when doing this though it may work fine testing on your machine.
- Several articles mention that DotNetNuke does this but I just looked at the code and it does not and this forum post suggests it does have serious performance impact according to Microsoft: "When discussing performance issues with Microsoft, they pointed out that moving the view_state using our code had serious performance impacts." So if they ever did this in the past they have removed it since then.
- In 4.0 .NET we will have better control over viewstate.