As I've learned on my years playing the game and reading forum posts from admins; basically it is forbidden to use software or anything that automates the game, like it plays by itself without needing you to actually play, from that we can conclude that such things you asked like rapid firing or biding keys is not a problem since it doesn't give any advantage or automates the gameplay.
About playing with multiple accounts, they never said playing on multiple accounts simultaneously is forbidden, paraphrasing what admins said about that: they don't care if you farm or play in 2-3 accounts at the same time as long as you play all them manually whether playing them at the same device or combining devices like pc+phone. But, it is forbidden to use a bot in any of those accounts or setting your pc so all your characters are being controlled at the same time by the same keyboard inputs. Also, if they detect you farming shiny pokemon in like 5+ accounts they directly ban all those accounts without warning.
That's what I have been learning by digging in posts like yours that got answered by admins, I was worried specially by multi account on the same device simultaneously because I like to play 2 accounts at the same time. One time I also binded ctrl key to another key in my laptop because it was broken and never had problems.