Then why put MIDI on at all? This is the kind of thinking we had before MIDI came out... Why would any keyboard manufacturer allow his gear to talk to gear from another manufacturer? Surely that would impact his sales?

But the manufacturers realized that, if they communicated over a common protocol, people with a Yamaha would buy a Roland, and people with a Roland would buy a Yamaha... and sales doubled (because Yamaha people weren't going to buy ANOTHER Yamaha, they already got one!). Actually, they much more than doubled.

The thing is, most of us have ONE arranger. The fact that it is so hard, complicated, and sometimes downright impossible to run two at the same time means we usually only play one at a time. So most of us BUY one at a time. But make it easy to run TWO at a time (or three), and sales would explode.

The manufacturers ALREADY scavenge sales from their TOTL by making incredibly capable, good sounding MOTL arrangers... The extra sales of more MOTL (or BOTL) arrangers we would all be buying if they actually worked together well would MORE than compensate for the few TOTL sales lost. And, TBH, I would imagine that there are many that would happily buy more than one TOTL arranger to use together IF THEY BLOODY WORKED TOGETHER!

The idea that this would do anything but explode arranger sales is ridiculous. We already saw what open communication did for synth sales.