While it's hard to imagine that 2013 Edition Arsenal would adopt something as pedestrian as a 4-4-2 formation, the French national team under Didier Deschamps has experimented with using both Benzema and Giroud at the same time in both World Cup qualifiers and friendlies in the past year.
In three matches since last September, Les Blues have won twice and outscored opponents 6-3 in those games -- though largely through the efforts of the team's most gifted midfielders.
Deschamps deployed Benzema and Giroud together in a 4-4-2 during France's 3-1 World Cup qualifier win over Georgia this past March -- their only win in the past six international games, which included friendly losses to Uruguay, Brazil, and Germany.
The motivation was, in part, to jumpstart Benzema, who alarmingly has not scored in the past year of international play, with ESPN noting it's been 1155 minutes since his last goal in a French uniform.
The pairing didn't directly lead to goals by either striker, but France had its biggest scoring output since beating Belarus 3-1 last September -- a game in which Benzema and Giroud also started together. Giroud scored in the Georgia match, on a header in first-half stoppage time (directing a free kick by MOTM Mathieu Valbuena, who also scored in the 47th minute and set up Franck Ribery's 61st minute goal).
In the Belarus match, Giroud was subbed off for Valbuena in the 61st minute, and though neither striker scored, Benzema did assist on Ribery's 80th minute goal to put the game away.
Last October, Japan beat 1-0 in a Paris friendly off a late Yasuyuki Konno goal -- the other game in which the duo started. In this game, Giroud started as the lone striker and Benzema, who came off at halftime, played on the left.
In the team's most recent match -- a scoreless draw against Belgium last week -- the team went with its more common scenario: Benzema starting and Giroud spelling him in the 74th minute.
In EPL matches with more defensive-minded teams, and in teams where the 6'0" Benzema might help the 6'4" Giroud win aerial battles (versus, say, a 5'5" Cazorla or a 5'9" Walcott), using Benzema and Giroud together could be a solid option, especially with Benzema's capacity to play second striker or on the wing. For Benzema, the move to Arsenal could give him more minutes against a greater range of international first-team players -- which could help France from being a group stage or Round of 16 casualty in Brazil next summer.
Now, there's just the small matter of signing him.