@Taztoy I always find it helpful when dealing with someone or something that I need to write to, to create a draft full of my anger irritation and as many swear words as possible and then file it away
until I can find a reasons calm phraseology
so
dear fucking ugly bastard fuckwits
i hate you beyond imagination
you are so appallingly awful at your job you ought to be put in stocks so I can chuck tomatoes at you
doubtless you have no concept of your failings nor no matter what will never have
I wish you terrible ill will bla bla bla
it has worked for me