The roll rate had little to do with it. You just have to accept the A6M refused to turn throughout the War, despite the constructions historians have made of this... It is a theoretical construction at odds with actual first hand observations.
An Allied pilot testing a crashed Zero and then saying "
Turns, that's what should be done with it." is
not a first hand experience of how Japanese pilots actually used it, even if the Allied conclusion is rationally correct.
The fundamental issue was that the Japanese Navy was hostile to circle fighting (to further distinguish from just doing quick 90-180 degree turns).
Do you think these guys were creative individualists who went against the doctrines taught by the most prestigious institutions in Japan?:
"
On October 21, 1943, the Group launched eight aircraft along with four Mustangs from the 530th on a big Japanese supply dump at Kamaing in Burma. The 530th squadron's P-51As met numerous Mitsubishi Zeros when they accompanied B-24s and B-25s on bombing missions. On the way down, I came up behind Lt. Geoffrey Neal, who was chasing a Zero [Mitsubishi A6M] down to the deck! I latched on to their formation and watched as he drove the enemy fighter right into the ground. The pilot of the Zero had tried everything to get rid of Lt. Neal except to circle fight. At this point, Lt. Arasmith had two confirmed kills, but the fight wasn't over…"-311th Fighter Group Unit history
I discussed this point with the Intelligence historian who (creditably) made a slight dent into this ridiculous historical myth, Justin Pyke (interviewed in the video I linked above). This is what he came back with:
"
My modest contribution to
the discussion regarding IJNAS pilots making use of vertical maneuver
and energy fighting stems primarily from my work digesting
intelligence reports describing Japanese fighter use in China from
1937-41. They certainly also engaged in horizontal turning duels when
they deemed it appropriate to do so."
The problem with this is... I did see one early WWII example of a Zero making circles, in Saburo Sakai's "Samurai!", where even the lighter A6M2 could
just stay behind a Wildcat, but this is one of
the rare examples of multiple circles involving the Zero. I have
hundreds of cases of the P-47 making 4 consecutive circles. Aside Saburo Sakai, I can't remember ONE involving the Zero...
The Zero
really liked vertical loops, that is for sure...
So basically Justin Pyke's bland assertion that Japanese pilots acted efficiently, and made circles when needed, is just that, an assumption. And it is disagreed with by a US pilot with actual first hand experience.
And Mr Pyke had the gall to disagree with him(!) in that video, concerning the pilot's assertion that slowing down and turning was inherently superior to speed!:
1:01:42 USN pilot after action report (1942): "
In my opinion, they [Zero pilots] had generally poor fighter tactics: Zeroes could not be shaken by us if they would chop their throttles and sit on our tails."
And Justin Pyke: "
Now I don't agree with his assessment that this was poor tactics. Hit and Run and energy fighting was just the way aerial tactics had moved around the world. You didn't want to dogfight all the time."
Yeah, except for P-47s making 4 consecutive circles all day 2 years later, and a FW-190D-9 pilot using only 60% power 3 years later. Other than that, it was all about
energy fighting, trust me Bro.
So he thinks he
knows better than the guy who was actually there?
As to the roll rate:
The roll rate had only a moderate use in combat, because once engaged in a turn rolling out was the most amateurish mistake you could make... The Germans, unfortunately for them, were very prone to this error, a mistake the high roll rate of the FW-190A only encouraged:
-Maj. Robert Elder, 24 March 1945 (P-51D): "
With this top cover to encourage me, I managed
to out-turn another FW-190, and, just as I was about 30 degrees angle off, this Jerry reversed
his turn (they are stupid that way) and I latched on to his tail at about 100 yards range. I got
strikes all over the plane and he caught fire in the air and crashed. (As I was shooting the above FW 190 down, another FW 190 got on to me and Lt. Colonel Bliekenstaff came down and shot him off. )"
Note that seconds after he reversed the turn, a friendly came behind the P-51s to help him out... That is why you never reversed your turn...:
View attachment 883595
-Capt. Glendon V. Davis, March 8 1944 (P-51B): "I turned into him and he (lone FW-190A)
swung around, almost getting on the tail of Lt. Smith, following me. I called to him to put down
flaps and turn with him, as I had 20 degrees myself.
We went around five or six times with the
issue very much in doubt. I could not quite get enough deflection to nail him, though
I was
firing short bursts trying to get him to roll out, which he was too smart to do."
Osprey "VIII Fighter Command at War, -Long Reach-", P. 31 (On the tactical significance
of using the roll rate in combat, Lt. Col. H. C. Craig):
"Once a turn is started in an engagement,
it is of the most importance, and safety, to remember
to never reverse your turn.
It has been my observation that a great majority of the
victories of my unit were made good when the Hun reversed the turn."
Even if you were losing a turn fight, you had a radio to call for help while the turn kept you alive and in one spot... That is the dynamic that mattered here.
That concentration definitely helped for Hit and Run, because Hit and Run forced such closeness that the wing guns went wide. But the whole point of turn fighting is that it gave longer windows at a greater range that was also constant. Which is why by 1945 turning was becoming the main tactic of everyone except the Japanese Navy... The Hellcat in 1945? Mostly turns, and it could turn with everything the Japanese had except the Oscar (and it certainly out-turned the Ki-84, to say nothing of how wide the margin was with the FM-2 Wildcat...). The late A6M5c was probably little better than on par with the Hellcat, but in one well-known account the A6M5b is badly out-turned by an FM-2 Wildcat (the last one to take off from the St-Lo just before it was sunk).