This is well done!

> Support error recognition and recovery.

I totally agree with this. You have to teach critical concepts a couple different ways in case one gets skimmed over or misunderstood. We rely on visuals for this--the text should stand independent of the photo / diagram, and vice versa.

I wrote a handbook on technical writing summing up what we've learned over many years of writing iFixit repair guides. https://help.dozuki.com/Tech_Writing/chapter/0