I am not sure what you mean. BIAB, (and also Real Band and Powertracks) are excellent at intelligently splitting a piano track into a logical and playable transcription using a floating split point.
This feature makes the transcription of two handed piano playing much faster, more accurate and generally superior to any transcription of piano music that the 'big boys' of notation software (Finale, Sibelius ..) can manage to produce. Of course, in other respects, BIAB does not match these other programs which allow many other features that BIAB has not implemented. Hence, the many calls for MusicXML which would allow exchange between music programs.

Doug
http://www.bushgrafts.com
https://www.youtube.com/user/jazz2511