#1
Hi I was wondering, what technique is used in the very beginning of just by radiohead?
because I'm learning the song...

I can hit single notes at such a high speed, however you have to strum power chords at that speed... And I feel like I need another technique to do that...

So do I? Or do I just need to practice?
Maybe it's my pick thickness too? (Which is fairly thick at 1.14 mm)

Thanks in advance
#3
It's just strumming really. You have to focus on economy of motion, try not to hit any other strings than the ones you need to. Also I believe you're wanting to play octaves. You shouldn't need a specific pick for a specific technique. Try to find just one that works for everything more or less.