So to ease listening, and to make iTunes' duplicate-finding feature work, I whipped up the following AppleScript. It sets the album to the original album title, and sets the Grouping to "The Complete U2." Oddly, the original files have the exact opposite settings, so the script really just switches them around. If others out there are wondering why the songs are marked in such a way, this script and four or five minutes of your time will stop the questions!
property oldPrefix : "The Complete U2 - "
on run
tell application "iTunes"
set theCompleteU2 to every track of playlist ¬
"Library" whose album starts with oldPrefix
log (count of theCompleteU2)
repeat with eachSong in theCompleteU2
set realAlbum to eachSong's grouping
set eachSong's album to realAlbum
set eachSong's grouping to "The Complete U2"
end repeat
end tell
end run
[robg adds: I haven't tested this one yet, as I haven't convinced myself to spend the cash on the whole U2 collection...]

