I had this same issue at a Marriott and a Renaissance that I spent all of my nights at to reach Gold, and finally, Platinum. As a Gold member, I received a CL room only once, and never knew to request the CL. It wasn't until I became Platinum and started researching what the benefits of status were that I started pushing back on unsatisfactory rooms. At some point I concluded that my corporate rate influenced the room I was given more than my room preferences (Note: no need to challenge my conclusion; chalk it up as my opinion, researched or not and let's move on). When I became Platinum, I started receiving CL rooms, automatically, and the elevator or adjoining rooms have been few and far between.