You've got two things going on here. First off, anything Boeing puts out in the AFM or MM is written in something they call "simple English". Supposedly simple English is easier for people who don't have English as their native language to understand. However it loses much of the subtlety that native English speakers depend on so it has the effect of making less clear to them. Whenever we came up with instructions or procedures that would go into the AFM or MM, we had to give it to another group who then re-wrote it in simple English (sometimes we didn't even get to review it afterwards to make sure they hadn't inadvertently changed the meaning). I suspect that's where Fire Handle became Fire Switch - internally we always called it the Fire Handle...
Secondly the lawyers get involved - for example a throttle cable doesn't break or fail, it "separates"...
