If you're worried that the magic might be ruined, ask yourself these questions*:
- Do I believe that garbage miraculously disappears?
- Do I believe that the parade floats continuously circle the parks, never stopping?
- Do I believe that the way things are for the park guests are the way they are for the workers?
- Do I believe that the workers somehow don't have the cares and worries of any other job?
- Am I under the impression that there is no support framework whatsoever for the park experience I enjoy?
If you answer yes to those questions, then yes, the magic will be irreparably ruined. However, if you enjoy the park experience and you wonder what goes into making it and you also want to be told some of the painstaking detail that went into making that experience, you'll love the tour.
I'm not a believer in magic, and being told the complete and total attention to even the smallest details (ones that would be otherwise completely unnoticed if they blew it off, like the shutters in Liberty Square) do nothing but enhance the experience, since much of it was stuff I missed just going through the park normally.
* I'm really not joking with these. From what I've seen from some on here, there may well be grown adults who are under the impression that such things may be the case at Disney, even if they are not the case anywhere else in life. It's like they think that everything, even backstage, is nothing but candy canes and unicorns. If you begin with the understanding that there's a mammoth support structure behind the veneer most guests see, you'll LOVE the tour.
