In the Boeing Flight Crew Training Manual (FCTM) in Chapter 5 under the heading 'Go-Around and Missed Approach - All Engines Operating' there is just this single line about the behaviour of the automatics
Note: An automatic go-around cannot be initiated after touchdown.
Further on in the same chapter under the heading 'Go-Around after Touchdown' there is the single sentence:
The F/D go-around mode will not be available until go-around is selected after becoming airborne.
In the FCOM Chapter 4, Section 20 under the heading 'Automatic Flight - Go-Around' there is one line:
The TO/GA switches are inhibited when on the ground and enabled again when in the air for a go–around or touch and go.
I have always felt there are many items in the Boeing manuals which have cursory or vague explanations of various systems or scenarios. Given the importance of understanding the inhibition of the Autothrottle system in the event of a rejected landing and especially in light of this accident the explanation in the Boeing manuals of this particular quirk of the system seems woefully inadequate.