Covering the ARC of your fire team partner is ok. In the first example, you would use that for a hallway or corridor with little chance of overhead fire. The Second example would be more adapted to a fire team doing a sweep where vertical threat is tactical challenge.
As a note, your fire team will not generally separate more than about 5 meters. If there is a need for a second corridor to be cleared, a second fire team would be brought in and then the whole process would over-lap, the point of each team would move with first example and the second man would move into position in a X movement to mate up with their fire team partner.
Don't bitch about you day or the price on something. A Canadian soldier died so you might enjoy today.