Busen, everything I said in one sentence! LOL
Exactly so with all MIDI software, processing a lot of MIDI data with a built-in lag to begin with on the limitations of the 8MHz 68000 Macs, was a lot to expect to begin with. Keeping up with the GUI, which was improved on the SE, but not significantly so, was of little importance to the intended purpose.
I remember when we got the Mac II, and it was as "magical" as using the iPad to watch a 20 track score flow by in real time with the music.