So as I am playing the tutorial, I notice that when attacking the Reb force of AS Johnson with The Army of Tennessee, that Sherman and McClernand's corps preceed Grant's unit into the region and engage the Confederates before Grant's unit (with a beaucoup of artillery) meets up.
This is with and without the Leader Modification mod that has been offered up. I've included a JPEG to illustrate - this is after the battle, which was pretty even up as regards casualties.
And I also notice that Sherman always arrives a day earlier than McClernand and Grant whenever they are traipsing about in Syncronized Movement. What is with that?