Yeah, good point. BIAB handles it like a shot. It's probably difficult for the program to make this happen, sustain a real track, unless they are already recorded that way, which I doubt.

My conclusions - it's a real bug that needs to be fixed.
When my BIAB arrangements are imported and played in Real Band, the chord instructions are ignored, except for the drums.
This results is goofy playback.
Editing is unthinkable - way too much work!
Worse - it makes it impossible to add new real tracks with proper results.

How do we get PG Music's attention and some confirmation about whether they intend fix to these things?
We discuss it here.
We may agree and/or disagree, but is it dust in the wind?