you've heard of some now :) But isn't this a bit like tourist submitting the address of a hotel where they're only going to stay a couple a days before island/mountain hopping?
Seems like it's mainly just to show the embassy that you have some sort of plan.
I highly doubt it. I went all over the country during a 6 week trip with a tourist visa based on an invitation letter. I'm pretty sure it's just a pile of red tape to be stored in some warehouse somewhere.