If anyone recognized it as a Dream Theater song, I'm sure they'd let you know. If I ever heard someone playing DT in a bar, I would be absolutely sure to let them know that I recognized it.
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In other news, I played some Frank Zappa in church today. Okay, just one measure, but it was some. I've been learning "Evelyn, A Modified Dog" for my own amusement, and it's in A, and starts with a wacky E7 arpeggio. Our opening song today in church is in A, and I was playing the piano for it, so I did the "Evelyn" arpeggio, then kicked into the regular song.
So it wasn't much, and I was the only one in the building who even knew what I'd done, but I did it, and yeah, I'm proud of it. I played some Frank Zappa, and segued into "Halle, Halle, Hallelujah!" (Frank would not have been proud.) You have to take these little accomplishments where you can get them.