Good Lord, anyone with two fingers and two eyes can press the two buttons together! My fingers are semi-arthritic and my eyes are brown because my brain is full of 68 years worth of accumulated doo-doo, and I can do it.
It doesn't have to be timed to the milli-second; the sequencer kicks in, or out, at the end of the current measure.
Don't buy the Korg for this reason alone, but "don't knock it if you haven't tried it!"
Crap, I can hit control-alt-delete together still.
Don't get me wrong, they COULD have made it easier.
It's harder sometimes to hit the shortcut button and, say Mic, to make on the fly adjustments, but I can usually do that too.
And a good thing is that you can do real time adjustments and save them while a song or style is running. Most arrangers won't multitask like this.
DonM

I thought of something else. The buttons are side-by-side. It's the same as hitting the plus and minus buttons together to set the default tempo or transpose values. You can do it, if you concentrate!