Am I understanding it right that your idea is that limitations were consciously introduced to remove possible annoyances when machine is acting puzzling to the user?

Slaved would mean receiving MIDI, not sending it, perhaps you've meant acting as a master?

707 has an additional limitation: "When the [707] Composer is transmitting MIDI message, the built-in voices do not output any sound". So if it would send MIDI in pattern mode, this would still prevent from using 707 sounds along with whatever is sequenced. This one is baffling too especially as 707 has a quick volume control section which would make removing any unwanted sounds easy... Or impossible if those controls would become dusty and couldn't remove the specific sound entirely anymore. Hmm...

Your topic from the year 2009 has reached my eyes. I respond to you now, 15 years later, informing you of my possession of the KORG Volca Drum, which was not made until long after your post, and is in equal parts interesting and frustrating. However, I have fluked my way into creating some listeable sounds, so it is still with me. These listenable sounds do not include any realistic cymbal sounds. Cymbals are a big part of being a drum, so I feel as if I have been taken for a ride by Korg, albeit not the nice kind or ride that a nice realistic ride cymbal would provide.

My Volca Drum lives on a diet of 6xAA batteries. I carry 2 sets (12x AA) of Sanyo (now Panasonic) eneloop rechargeable batteries so the clueless tinkering...I mean...uh...the serious application of my deep sound design knowledge, is not cut short by silly battery life limitations. My Volca Drum & I enjoy travel: long, picturesque road trips feature heavily, travelling to and from the livingroom couch.

oh really? 707 doesn't play own sounds in Track mode, whilst sending out MIDI? wow didn't know that.
when i first saw it & bought it, i thought it could be the ideal MIDI drum programmer (talking 1996 here, there were none of the modern alternatives there are today, different world).

it must have been as midi slave because i was comparing to the DR550mkII which only has MIDI In.

i noticed it running Bassbot with DR550mkII, just the two of them, with Bassbot as master. ie: unreliable sync start with Pattern, tight with Track.
i think someone else has to verify this; i don't want to carry on perpetuating this idea if it was just me, and only that time

it would be a matter of how the core clock works, and maybe something they kept down through the versions ( ... doesn't sound very likely does it? )