Cross grain movement(good term BTW,) was a bit of brain twister for me when I reading the urban combat section of BMR. I hadn't seen the City Hills 1/2 or City Grid/Park 1/2 maps so when I read about streets and buildings and cities, I thought about Manhattan, with streets at right angles. Moving uptown is easy but cross street? If you don't want to risk skidding, even a Firemoth, but would be limited to about 5 hexes of crosstown movement. Then I saw a hex based city grid and it made a lot more sense.