It's been a while since I read it and I have a digital copy but here's an excerpt from the beginning of chapter 15:

> The reality of the war in China was far different. The Chinese army had not fought a serious battle with the Japanese since 1938. In the western sense it was really not an army at all, but a coalition of warlord bands scattered over twelve “war areas” which roughly corresponded to groupings of the old provinces of Imperial China. Each local warlord functioned as war area commander; in this capacity he exercised both civil and military control. Many of the warlord armies were ill-equipped and poorly trained. They seldom fought the Japanese, serving mainly to buttress the power of the war area commander instead. The core of divisions directly under the control of the generalissimo were better trained and equipped. But even they were undermanned and lacked artillery; in most cases they were commanded by officers chosen more for their loyalty to the generalissimo than for their military prowess.6

> “ ‘The general idea in the United States that China has fought Japan to a standstill and has had many glorious victories is a delusion,’ ” wrote a member of the American military mission to China. “ ‘Japan has generally been able to push forward any place she wanted to. She has stopped mainly because of the fact that a certain number of troops can safely hold only a certain number of miles of front. . . . The will to fight an aggressive action does not yet exist in the Chinese Army.’ ”7

> Corrupt, demoralized, inefficient, and oppressive, Chiang’s Kuomintang government was uninterested in “aggressive action.” It was interested in surviving the war against Japan with its armies intact, ready to deal with the generalissimo’s rivals among the warlords and his far more dangerous enemies, the Chinese Communist forces of Mao Tse-tung. A handful of Americans on the scene, like Ambassador Clarence Gauss, a dour New Englander with few illusions, attempted to enlighten Washington about the actual state of things, but had no discernable impact.8

And here's some discussion of Mao found in chapter 17:

> Yet the Communists profited from their mistakes. Under the leadership of Mao Tse-tung (who blamed the setbacks on his rivals, whom he then purged), the Communists concentrated on guerrilla warfare by small, widely dispersed units; their strategy emphasized the importance of building a solid base of support among the peasants by living among them and sharing their burdens and hardships.38 As Japanese units were gradually withdrawn from northern China to meet the Allied attacks in the Pacific, the Communists stepped up their guerrilla attacks. The Ichigo offensive brought them still more opportunities. By the fall of 1944 the Communists controlled large portions of four provinces. Their base areas were established in territory supposedly held by the Japanese but where the latter were too weak or too thinly spread to exercise any real control.

> At the start of the Ichigo attacks, Vice President Henry Wallace, on a special visit to Chungking, had urged that the Communists and Nationalists attempt to settle their differences in the face of the common danger and that an American military mission be allowed to visit the Communist base areas in the north.39 Chiang reluctantly agreed. The so-called “Dixie Mission,” composed of a small group of American soldiers and foreign service officers under Colonel David Barrett, arrived at Yenan in July 1944.

> The men of the Dixie Mission were favorably impressed by the Communist display of energy and aggressiveness. Communist leaders like Chu Teh, Chou En-lai, and Mao Tse-tung—with their informality, homely manner and apparent frankness—struck the Americans as a favorable contrast to the traditionalism and ritual formality of Koumintang leaders in Chungking.40 Discussions were held; plans were made by Wedemeyer’s headquarters and the OSS for military cooperation between the Americans and Communists, and for the Communist forces to receive lend-lease military supplies and American military instructors. (The OSS had, in fact, already begun some elementary small-arms and demolition training for Communist soldiers.41) All these projects came to nought, however, because of the strong opposition of General Hurley who, shortly after Stilwell’s recall, had replaced Clarence Gauss as U.S. ambassador to China. Hurley was in the midst of tortuous and ultimately futile negotiations to persuade the Chinese Communists to enter a coalition government under Chiang’s leadership; he wanted to use access to military assistance as a bargaining tool.42

I'd say that the comparison of the number of traditional battles fought that you're offering as evidence does not make sense given the nature of the two forces.