Let's consider that ideas for a moment, we'll tell the users to constantly switch back and forth from the Desktop screen to the Start screen. Hmmm...That sounds plausible doesn't it. Let's see it's not here so let's go look over there. Well, it's not there either, now let's use on of the "hidden" features (i.e. non-visible) to place it on one of those two screens and try to remember where it is. This instead of using a simple desktop and/or the Task Bar to store all the shortcuts I use every day. What a grand idea that is.
(Just so you know, the sarcasm is directed at Microsoft, not you.)
Even though I enjoy this little tet-a-tet, the main point is "Choice" which is something everyone is asking for. Will there be a downside to that choice, presumably, Yes. But allow the users to make that choice themselves. It simply appears to many of us that Microsoft is trying a one-size-fits-all approach with their new offerrings which many disagree with. And as you can probably surmise at this point, I happen to agree that this approach seems somewhat shortsighted.