Key chords is the bane of keyboarding.

There are 3 types of keyboard shortcuts to invoke commands in software:

• ① Single key ➢ for example: 【F1】, 【⇞ Page △】.
• ② Key chord ➢ for example: 【Ctrl+c】, 【Ctrl+⇧ Shift+z】, 【Alt+F4】.
• ③ Key sequence of single keys or chords. ➢ for example: on Microsoft Windows, 【F10 e c】 for copy, or 【Alt+Space c】 to close window.

of these, in terms of efficiency and hand health (Repetitive Strain Injury), the single key is the best. Key sequence of single keys is second best. Key chord is the worst.

Key chord is the most hard on hand health, but is also conceptually the most convoluted.

i remember in around 1991, when i first learned about key chord on the Macintosh Classic. I remember thinking, it's strange. You have to hold ⌘ Cmd first, then press the key c, then, release c, then, release ⌘ Cmd. It must be in that specific order.

A more natural way is either key sequence, or real chords. Real chords, meaning, pressing several keys together but you don't have to worry about which to hold or release first. Stenograph machines are like that.