Alright guys, I just want to add a to this section. The key song here is eruption. I have read countless guides about this song and everyone says to use the starpower in the same spot. I just want to say that you shouldn't use the starpower when people tell you to, because odds are they used it on their strongest part in the song. Just as a personal testament, i played the song for 3 hours straight trying to get this achievement, and eventually i decided that the tapping part was actually my strongest part, so i decided to save up my starpower for the end of the song and lo and behold i got the 5 stars, so that is my first tip. Save the starpower for the parts of the song you are most confident with because that is where all of the points are going to come from.
For my second tip, as to the tapping part, just tap your left middle finger and your right index in an EVEN motion. don't try to match the pattern of the section EXACTLY. if you try and get an even motion going, you can still hit all the notes just fine and you'll still clear the section. I was able to pull a 5 star from a 3 star off of the tapping part alone because i could do it missing ALMOST no notes, and since i saved up my starpower, i had it activated for most of the section. So in short, just save the star power for when you are most confident and when you tap, keep a constant motion going. Just thought i would throw that out there.