Why did the Wright brothers take steps to increase the amount of vertical surface area in front of the CG on some of their aircraft?
Could this have actually improved the flight characteristics in any way that could not have been equally well accomplished by slightly reducing the size of the aft-mounted vertical fin or all-moving rudder?
(End of actual question)
Supplemental content that may help inform an answer--
If the goal was a decrease in "weathervane" stability1, wouldn't reducing the size of the vertical fin or rudder aft of the CG have given the same result, with less drag?
If the goal was to prevent sideslip, wouldn't increasing the vertical surface area forward of the CG actually be counterproductive? Wouldn't increasing the vertical surface aft of the CG have given the desired result?
Did the Wrights have a notion of that sideslips were caused in part by gravity trying to "pull" a banked aircraft sideways through the air toward the low wingtip, while the aircraft had insufficient side area to resist this "pull"? If so, wouldn't this have been a faulty notion of the fundamental cause of sideslips, and of the balance of forces in a non-slipping (coordinated) turn?
Or did the Wright brothers have some conception that it was desirable to maximize the sideforce generated during a sideslip for some other reason? If so, does this conception really make any sense from a modern perspective?
Did the Wright brothers have a misconception of the basic nature of spiral instability, leading them to mistakenly suspect that an increase in the sideforce generated by sideslipping, rather than a decrease in "weathervane" stability along with an increase in dihedral, would be the most productive approach toward making an aircraft less prone to "winding up" into a steeper turn?
The Wrights left many letters and other written notes, so it should be possible to answer these questions with some degree of authority.
Related quotes from outside sources:
"1905 Flyer III: Semi-circular [vertical] "blinkers" between the surfaces of the canard prevent the nose from dropping in a turn. With this aircraft, the Wrights were able to fly until their fuel ran dry. In 1908, they adapted the Flyer to carry the first airplane passenger." -- From http://www.wright-brothers.org/Information_Desk/Just_the_Facts/Airplanes/Wright_Airplanes.htm
"The crash convinced the Wrights to make radical changes to the aircraft design. They almost doubled the size of elevator (in front) and rudder (in back) and moved them about twice the distance from the wings. They added two fixed vertical vanes (called "blinkers") between the elevators to serve as stabilizers and help prevent the Flyer's tendency to slip or slide sideways in a turn." -- from http://www.wright-brothers.org/Information_Desk/Just_the_Facts/Airplanes/Flyer_III.htm
1)http://wrightbros.org/History_Wing/Wright_Story/Airplane_Business/Airplane_Business_Intro_images/1911_Exp_Glider.jpg , from http://wrightbros.org/History_Wing/Wright_Story/Airplane_Business/Airplane_Business_Intro.htm
2)http://www.wright-brothers.org/Information_Desk/Just_the_Facts/Airplanes/Wright_Airplane_images/1905_Flyer_III/1908_Flyer_III_at_Kitty_Hawk.jpg , from http://www.wright-brothers.org/Information_Desk/Just_the_Facts/Airplanes/Flyer_III.htm
3)http://www.wright-brothers.org/Information_Desk/Just_the_Facts/Airplanes/Wright_Airplane_images/1905_Flyer_III/1905_Flyer_before_rebuild.jpg , from http://www.wright-brothers.org/Information_Desk/Just_the_Facts/Airplanes/Flyer_III.htm
4)http://www.wright-brothers.org/Information_Desk/Just_the_Facts/Airplanes/Wright_Airplane_images/1907_Model_A/1909%20Launch%20in%20Italy.jpg , from http://www.wright-brothers.org/Information_Desk/Just_the_Facts/Airplanes/Model_A.htm
5)http://wrightbros.org/History_Wing/Wright_Story/Airplane_Business/Airplane_Business_Intro_images/Vin_Fiz_Takes_Off.jpg , from http://wrightbros.org/History_Wing/Wright_Story/Airplane_Business/Airplane_Business_Intro.htm
6)http://www.wright-brothers.org/Information_Desk/Just_the_Facts/Airplanes/Wright_Airplane_images/Model%20CH/1913_CH_at%20anchor.jpg , from http://www.wright-brothers.org/Information_Desk/Just_the_Facts/Airplanes/Wright_Airplanes.htm
1-- In this question, "weathervane stability" is used to mean "yaw stability", i.e. "directional stability". No implication is intended that an aircraft in flight "feels" the external, meteorological wind, apart from the effect of sudden gusts.
Addendum-- it seems possible that in some cases, part of the motivation for installing these vertical surfaces may have had to do with the Wright brothers' experiments with an automatic stabilization system, which included a pendulum, which would only give useful indications if the aircraft tended to generate a significant amount of sideforce whenever it was banked and turning. So the present question is confined to aircraft that were not being used for experiments with the automatic stabilization system and were not given specific design features for the purpose of helping the automatic stabilization system work better.