I'm looking at Radiohead's Karma Police, and I see this:

Due to the super anal-retentive tablature, it looks like this was lovingly plagiarized from a store-bought tab book.

Can I infer that Thom is doing these three things:
  • He strums down when every string in the chord is struck?
  • He strums up when mostly lower strings are struck?
  • He strums down when mostly higher strings are struck?

Can I also assume that Mr. Yorke is taking the "path of least resistance" with his strumming pattern? To put it another way: if the above three points are true, then should I try to imitate his strumming pattern for the greatest efficiency?

I'm not looking to copy Thom exactly here. I'm just trying to get a feel for the proper arm movements a complicated (well, it's complicated to me!) strumming pattern.

That does look very much like it's copied from a book, i've got the bends guitar book and it all looks like that.

For the strumming listen to the intro because you can hear the strumming better and i think the strumming is similar for the rest of the song. Also, use the rythm in the tab cos it looks pretty good and just use the whole chords ocasionally missing out the top or bottom 2 strings.