Doctor M said:
Wait, now I'm confused, you need to use double plus signs? I've always used a single one. Is there a difference in what that does?
As Moth3r said, it is how the audio is handled. As I said, I don't think it makes a difference if with video-only splicing: I just do it this way out of habit.
I'm ashamed to say that I didn't know about DeleteFrame(). That would probably be the best opion.