Well, no mate, in a word.
The two speed DeHavilland prop provided a greater top speed than the CSP.
The advantage the CSP gave was in rate of climb, which was deemed more important in a short range interceptor designed to stop high flying bombers.
In fact, from memory (I'll check and come back), the original wooden fixed pitch prop provided even more top speed than the 2-pitch DeHavilland, but there were lots of other factors involved such as all up weight which became progressively heavier. Interestingly though, the DeHavilland prop was the heaviest of the early props, and required a lot of ballast in the rear fuselage in order to maintain the centre of gravity. This was because it was a metal prop, whereas the fixed pitch and surprisingly the CSP props were wooden.
Interesting stuff if you like buying books and that!
