Rather than manual sync, then the songs should be removed from your iPod without having to manual delete them. Works as long as as those songs aren't on any other playlist. You have to be careful with autosync, though. If you have stuff on your iPod that isn't in your iTunes library, it will wipe that out. When you initially do it, you'll have to stop it right away (but don't disconnect, just click on the "x" that's in the progress window) because the default is to put the entire contents of your iTunes library on your iPod. Obviously that's not what you want. Once you stop the autosync, go to your music tab in the main window and check off the playlists you want on your iPod.