After the game was played it was thought the game vindicated Shipley's claim that the attack was good despite the fact that Capablanca, after considerable analysis, determined it was inferior. This agreed with Janowsky's assertion that the attack was unsatisfactory for white. As for the belief that this game vindicated Shipley's claim, it was based, as was often the case, on the result. It used to be common practice to praise every move of the winner and criticize all the loser's moves. Things are not often so simple.
While visiting New York City Shipley met Janowsky at the Manhattan Chess Club. When WW1 broke out Janowsky, Champion of France, was in Germany taking part in the Mannheim tournament when he was interned with the Russian masters, but later escaped into Switzerland and finally came to the United States.
Shipley and Janowsky were discussing the Gledhill Attack and Janowsky stated the attack was new to him because he considered the French inferior for black and never played it. So, he had never made a serious study of it. They set up the position after the seventh move and Shipley played 8.Qg3 which Janowsky met with 8...Ng6 with the idea of freeing his dark squared B the task of defending the N on f5. Janowsky concluded that black then had the better game, believing white had sacrificed a P for very little compensation. Shipley disagreed.
At about that time Capablanca showed up and Shipley and Capa played several skittles games with Capa adapting Janowsky's suggest line. Naturally, Capa won and so Shipley believed he was apparently wrong in his judgment of white's chances. But, to more thoroughly test the variation a correspondence game was arranged with Janowsky agreeing to take the black pieces.
After his 9th move (9.Ndb5) Shipley believed he had the better game and if Janowsky agreed, the game should be abandoned. Janowsky disagreed and replied, “Relative to your remark that you think you have the better of the game, I do not agree with your position.” Capablanca wrote, I believe that white has a chance, but also black has the best of it, nevertheless.” Shipley admitted that the opinion of these two players was superior to his, but believed that it was always possible that an “offhand opinion given by the best masters may be shaken by thorough analysis.” Although Shipley is listed as playing the white pieces analysis appearing in the American Chess Bulletin makes it clear he was in consultation with other strong Philadelphia players.
The Gledhill Attack remains pretty much unexplored although a series covering it, Secrets of Opening Surprises, by New in Chess is available. Yorkshire Chess History site has an interesting article about Walter Gledhill HERE.