A potentially dangerous Request.Form value was detected from the client in .Net 4

Question

So, this whitepaper describes one of the breaking changes in .Net 4 to be the error message "A potentially dangerous Request.Form value was detected from the client in", and the fix to enter into the Web.config file

I have 2 problems with this. Does this mean that any website where I want a wysiswyg editor like tinymce, or ckeditor, the requestValidationMode has to be 2.0? What benefits do you lose out on in this case? (if I lose no benefits to setting requestValidationMode to 2.0, why not set it by default so it doesn't break anything?)

In 2.0/3.5 I was able to set ValidateRequest on a page by page basis - this is of course still possible in .Net 4.0 , but in order to set it on a page level, I have to make a site wide change? Does this not seem entirely backward?

Have I got this right/is this as rubbish as it sounds, or have I missed something?

Answer 1

seems to be already discussed in A potentially dangerous Request.Form value was detected from the client