Great questions, stlram. I'm going to look into confirmation around this and will let you know.
There IS an indirect link -- Click on Bill Marriott's blog link on the bottom of the MRI page. Once it opens, scroll down to the Marriott logo at the bottom of the blog page. Click on it, and Marriott.com will open up on a new tab. You may have to re-enter your password, but then it's clicking between tabs.