Example of Aimed Fire at Infantry?

Question in the newer Battlegroup Rule Book (P. 29), "Example of Aimed Fire at Infantry"...

It describes the first target as the infantry squad in the cover of a wheat field, which hasn't fired, "so the roll needed is a 3+" in order to observe. The observation table on P.26, however, states "Obscured Infantry..... 4+". I don't believe any modifiers apply. Am I missing something?!?

Thanks!

Could be an error in that example, seem to remember a previous discussion that one had a mistake in it... will have to check.

Oh... Thanks, Piers. Just wanted to make sure that I hadn't misunderstood a fundamental rule.