I've posted this before, but for me the problem of the "Senior/Kleen Ream" that cannot expand to do a 360 degree ream is easily overcome by setting it to the smallest possible diameter, in which case the reamer can ream anywhere inside the bowl. I do 3 or 4 twists of the reamer, or more, anywhere I find appreciable cake and then move on to the next high spot.
Although doing this allows me to do an approximately 80% effective job, it doesn't address keeping relatively low and high places in the cake from being so, even after I've gotten out what I can see as high places. There have been a significant number of posts in this thread about the importance of having a reamed but uniform thickness to the cake left in the bowl.
I'm going to have to look into that.