yes but its even easier in RealBand. select the track, select the bars you want with the 'from to' fields and then choose your RealTrack soloist. you can even use mutiriffs to get different versions to audition and choose. then select the next section of bars and do the same again using a different soloist.

once you've got a song roughed out, RealBand is the easiest way to add bells and whistles.

BIAB is the first stage. to get some things done in BIAB you need to go through complicated stages when in RealBand its easy and simple.

As Charlie says it's possible to stay in BIAB but it's much simpler in RealBand. But each to their own - I just find it easier to swap to BIAB's sister program designed to do all (well nearly all) the things a DAW can do with the functionality of BIAB still available.