I found that article too in my searches to find a solution to this problem. However, just as with the Adsense for Search, I am not willing to give up the benefits of .NET. I'm using Adsense on most pages. I used my dial-up account to check and see if ViewState slowed things down too much for dial-up users and it didn't.
For their free Google search box they provide Web APIs. I suspect they will eventually offer that option for Adsense and Adsense for Search. I got a much more positive reply back from Google today stating that Adsense was a new program and that they would pass my comments about ASP.NET on to their team.
Meanwhile, I've decided to use Application_BeginRequest in Global.asax.cs to output the Google code if certain conditions are met. Although I can't control where
the box appears (it appears at the top of the page - or the bottom if I use Application_EndRequest), at least I can control when
it appears programmatically.