Charlie,
Isn't that for "track thickening"?
I believe OP is requesting for more "regular" mixer tracks on wish #1
So life is less complicated...
That's how PG Music markets it. This feature was subject to 2020 version PG Music staff enhancements of the Medleys feature. Medleys have been around for years and though it's listed in the 50 new features, it's really an enhancement of an existing tool. This year they added volume automation and panning per track which is what specifically allows the thickening feature. It does a lot more than that.
I started to speak about it over on another thread you posted regarding Multi riffs, freezing and regeneration but it was off topic and inappropriate for mentioning in that discussion and the others because the focus of those threads deal with programming and not existing audio tools.
In that thread you said, "I have a feeling that just do a "bar freeze" might be complicated because of the algorithms and "tails" of a line, so at the end it plays smoothly. These artifacts and undesirable results often can be heard when trying to "change RT" at the bar. Doing it as "mute" at the bar, solves that." and "However I strongly feel that even if the feature of "bar freeze" arrives, it would not sound smooth. Most likely it would sound "pieced". Not because of programming, but because of what Real Tracks are - audio... I do fear that they would sound abrupt as often happens with "change RT at the bar" option. But what I described, should take care of roughness." You nailed it by identifying the ... audio... aspect of the issue.
Muting does not always fix that issue and often times, muting does result in abrupt endings. But programming an audio transition does correct those transitions. Notice the last sentence in the first image I posted where 'smooth transitions' is mentioned. It appears that Smooth Transitions are programmed into BIAB's core program. If you program an instrument change using two instruments on the same track, the BIAB algorithm reads ahead of the Chord Chart and 'sees' the coming change and chooses audio to play a smooth transition. Note that BIAB in this mode treats Silence as an instrument. Plan ahead and you can program a smooth transition using silence for the track to transition to. In my experience, it's never failed. What appears to be a deal breaker issue for some, it's an audio edit rather than a Chord Chart edit.
But there are additional editing features that become accessible when you begin using audio in BIAB. Understanding that RealTracks in the BIAB are not audio until the file is played and not saved audio until the file is rendered there is a marked difference to how BIAB treats RealTracks and recorded audio. This enables an artist to combine medias of different types and compile them onto a single track. You can have MIDI, MIDI Super Tracks, RealTracks and recorded audio reside on the same track. Also understand the audio features and audio files I'm addressing are handled different than the programming wishlist items that are requested in four different threads currently. Those are legitimate programming requests but those requests, multi riffs, freezing portions of a track, generating a specific portion of a track, combining different media to the same track, converting mono to stereo and stereo to mono, thickening, bar to bar regeneration are all available in BIAB now by working in a project that expands into audio editing in BIAB rather than exporting out to a normal DAW, including RealBand for some edits. BIAB creates cross fades, transitions, plays multiple instruments simultaneously or independently on a single track.
BIAB has a specific feature that bridges between how BIAB normally functions with the BIAB Mixer Channels and audio. This feature is best identified as a single project specific User Track rather than the common understanding of User Tracks which are BIAB users version of home recording RealTracks that react to Chord Chart chord changes and key signature changes the same as a RealTrack does in a song. APT's are specific to the current project, and chord progression. But they also react to Style changes, instrument changes, instrument media type changes.
PG Music calls these single project User Tracks - Artist Performance Tracks. APT's can be used with the melodies feature, bar settings, song settings and any other setting in BIAB and used within the Mixer to create dozens of instruments across dozens of tracks using dozens of Styles playing independently or simultaneous instruments throughout the song. APT's allow normal audio created by users to reside on any other BIAB Mixer Legacy Channel than just the one Audio Channel.
Although BIAB is not a digital multi track recorder, APT's allow it to function as one.
Although BIAB is not a DAW, in conjunction with the single audio track in BIAB, APT's allow BIAB to function as a DAW and access the editing menu in my image above.
Regardless of the type media residing on a Mixer Track, the track can be converted to a Performance track by Rt. Clicking on the track, Track Actions\Save track as Performance File (wav\wma). Choosing this action saves an audio track, freezes the track, renames the track and the channel color changes to orange. Sometimes it's preferable to save a track as an APT rather than just a freeze a track because an audio file is also saved in the process. Johnjohnjohn noted in a comment in the other threads that opening a BIAB project in RealBand and RealBand does not import frozen tracks. That's true, but saving a BIAB project with tracks saved as APT's rather than frozen creates a audio file that exactly matches what would be that 'frozen' track if RealBand did honor that setting and that saved APT wav/wma file can be imported into the RealBand project.
To close, in response to the OP's request, using Medley's audio feature results in expanding the seven normal Mixer Tracks to as many as 70 virtual tracks in regards to RealTracks (which he specifically asked for) although practical use would not likely ever need that amount. Activating Melody's opens a Mixer for inputting your selections. I hope I haven't overstated my case but this seemed to be the most appropriate thread to make the case... Either way, I appreciate your patience in reading this far.
I created an example audio clip that's about a minute that uses a 'frozen' section, Replaces a MIDI instrument with a guitar solo that was comped from Three RealTracks of the same instrument (similar to your image on the Multi Riff post), has three smoothed transitions where BIAB plays instrument 1's ending simultaneously with Instrument 2's beginning and also has a transition starting several notes early on a bar. There's also several bars of the guitar comp that I programmed the two guitars to play simultaneously in the middle of the solo.
