Bulge '44 - Movement Wrinkle

[Xerxes77]

The cost of crossing the stream for a Hard Halftrack is 30, so in theory the unit should not be able to enter the hex.

However, in practice I've seen units use up their full movement allowance to legally move at least one hex, even into terrain and across hexsides that would add up to a higher cost. As far as I know this is not explained in the manual.

At around 21:45 you expect the movement cost of crossing the bridge to be 7 yet it's 6 -- I believe that's because you're crossing an engineer-laid bridge instead of a hexside bridge, so maybe the MP cost is 0? On a related note, what kind of bridges do engineers build, are they heavy bridges? Again I could not find answers in the manual.