So when you click a button on the G600 (and most other mice with side buttons), the button fires when you press down, just like the Mouse 1 or Mouse 2 button. On the G600, there is a third click button to the right of the right click, which is called G-Shift. When pressed, all of the side buttons have secondary assignments. Since you have to hold G-Shift to access this other layer, the macros are often referred to as chords in mouse customization software like Steermouse, since it requires two buttons to fire.
To configure this, you need the G-Hub software, which is in a nightmarish state on macOS. To get around this, I use Steermouse. Steermouse lets me get around this, however with one trade off. If a side button has two assignments (one when pressed by itself, another when pressed with the G-Shift), then the button does not actually fire when its pressed, but instead fires when the button is depressed/let go of. I imagine this is just how Steermouse handles buttons which have more than one assignment.
I haven't found a suitable replacement that is as robust as steermouse. Its one of the first apps I install on my mac, but this is one killer feature that I've only found in the G-Hub app.
I believe the poster means that the macro operation is that of an astable multivibrator, whereas they would prefer that it be that of a one shot multivibrator.
