Honestly, it'd probably help if they listened to the Entente advisers as well. OTL they just blew them off as not knowing anything about how to fight - which resulted in rather nasty casualties.
"close adherence is urged to the central idea that essential principles of war have not changed, that the rifle and bayonet remain the supreme weapons of the infantry soldier and that the ultimate success of the army depends upon their proper use in open warfare" General John Pershing, 19 October 1917.
One evening I had to give a lecture on 'The Attack' to the whole Regiment's [119th Infantry] Officers in the Town Hall, Yeuse. I mugged up the Army's official pamphlet and duly held forth, adding a few personal experiences and lessons. When I had ended the old Colonel, dressed more like a sheriff than a Colonel, heaved himself up onto the platform and said, "Gentlemen, I'd like youse all to accord the Scottish Major a hearty vote of thanks for his verra interesting lecture." Then he shook his finger and went on, "but I'd have youse guys remember the British have been trying these tactics for near four years and they ain't done much damn good!" (Captain A.F.P Christison, MC, 6th Cameron Highlanders)
"The Brigadier rode up whilst this show was in progress and joined the group of officers where I was enlarging on the Ox's commentary. I was receiving a sneering reception, the general opinion being that American troops would storm their objective without bothering about such fads as covering fire and barrages, etc.
"In any case it doesn't require much training or practice to do a show like that," commented one officer.
The Brigadier was on him like a knife. "Very well," he snapped. "I should like one of your platoons to give us a demonstration immediately."
The result was a complete fiasco. The men were willing enough but they simply did not understand what they were trying to do. I strolled round to where the Lewis gunners were stationed on one flank. They were trying to fit the magazine onto the gun upside down! The riflemen were shooting indiscriminately in every direction whilst I decided to keep as far away from the bombers as possible. I should not have been in the least surprised had there been one or two casualties. When they had finished the General let them have it hot and strong, pointing out what would have happened had they been facing a real enemy..." (Captain A.O Pollard, VC, Honourable Artillery Company; compare the complex tactics the British are attempting to teach the Americans to the basic "rifle and bayonet charge" tactics the Americans seem to be set on).
Of course, as per RobC, it might have resulted in a more decisive end to WW1:
The reason the war was ended by armistice was largely due to the fact that the US army "is not yet organised: it is ill-equipped, half trained, with insufficient supply services. Experienced officers and NCOs are lacking... The French and American Armies are not capable of making a serious offensive now. The British alone might bring the enemy to his knees. But why expend more British lives- and for what?" (Haig at the War Cabinet, 19 October 1918). As such- though I apologise for the pedantry- a better US army might have ended the war later but more decisively with an advance into Germany.
So... not a bad outcome, overall. If you have more than one coherent army capable of offensive into Germany, that is.
Heck, might even butterfly the French mutinies...