I believe it's required, I've had issues without it myself, ex. http://world.episerver.com/Forum/Developer-forum/-EPiServer-75-CMS/Thread-Container/2014/3/Exception-after-deleting-a-non-used-tab-from-admin-mode/, Johan Björnfot wrote to me that I have to make sure to have it set to true.
I don't think they would test this without a requirement/bug report, so it would be in the documentation... Probably :))
Couldn't find anything in the documentation. But seems to be a requirement as per Johans answer in your thread. Thanks.
Can't mark your reply as an answer :(
Another bug on the world.
I do agree that this should be a part of documentation. It's there when you install a website from a scratch, but if you are generating a connectionstring from server explorer in VS, you don't get it by default and you really need to know about it to add it back (or you hit a bug and realize).
I'll ping Andrea about it, so she can add this information to the documentation.
We've run a website without MARS for a while, but now it's throwing errors that a DataReader is already open and must be closed first. So, is Episerver tested without MARS or should it always be turned on?