I'm sorry, but SMF's have only been around since the advent of MIDI (mid eighties) and only practical for many since the Sound Canvas in the early nineties... (or MT-32 just prior)

In the meantime, home organs had auto accompaniment since the seventies. Arrangers in one form or another have been around a LONG time...
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An arranger is just a tool. What matters is what you build with it..!