Well, Kwiatek is not only talking about +12 boost. The document indicates that a Merlin III with 100 octane fuel has the same engine power (look at the mentions hp rating and compare with that of a Merlin XII
here) and limitations as a Merlin XII.
However this
document doesn't support this. It states that 3.000 rpm and any boost over 6 1/4 is only allowed for 5 min for a Merlin II/III. "Climbing" power is by definition allowed for 30min or 1 hour. See the contradiction?
The main difference between a Merlin III and XII is the of 70/30% water/glycol coolant which allowed the higher power and limits of the Merlin XII. Maybe this engine was operated at with that coolant?
Kwiatek can you give some more information about the document? What is about and what is on the other 39 pages?