Coincidence by Design?

I was driving back from a tap-house with a friend when a certain part of DJ Tiësto's live show at Dance Department in 2001 started playing over the vehicle's stereo system. It's hard to find a recording of this, and it's a trance track, so it's all one massive song. Still, I turned up the volume starting at 45:46, and showed my friend the melody that played.

Directly after that, I pulled out the CD and inserted Mutter, Rammstein's 3rd album. I advanced it to Ich Will, and had him listen to the bridge verse. Sure enough, a very similar melody played off of Flake's keyboard. We're talking 95% the same. Mutter was released before DJ Tiësto's live show by about 6 months. Did DJ Tiësto copy Rammstein, or was it simply a coincidence?

The idea I'm actually trying to bring up here is the point which came up seconds later in that very car ride. With the amount of musical groups out there, the finiteness of the musical spectrum, and the amount of popular material out there, it is nearly impossible to create original musical material. Everything will sound similar to something, be it Ich Will, Beethoven's 9th, Dethklok, or Vivaldi's Seasons. The very tune you may have idly whistled this morning could be strongly copyrighted by a very malevolent musical group. This can lead into a popular topic of what constitutes original content any longer, and does RIAA's authority apply. If so, where? Anyone who knows anything about this, please feel free to post in the comments.

My favorite bit of unoriginal content in Rammstein would be in their song Moskau. Those who have played Half-Life and Half-Life2 will remember the Gauss gun, a gun which would wind up with a very distinct sound. This sound can be heard throughout the song, but most noticeably at 3:10, end of the bridge. In my eyes, this shows that Rammstein, if they don't like us Americans, they at least like our video games.

Winding up for a busy day by listening to good music,

-The0