I do that all the time, works like a charm.
In fact, most of the bigger places would benefit tremendously from the "one point source" method as well. But as we all know, speaker towers on both sides of the "stage" look soooo cooool
As do subs under the tops as well.
"Two towers spread the sound better" is usually BS since the distance between the towers is great compared with the dimensions of the space we're playing in. All kinds of reflection and arrive time differences just create a sonic mess.
Good luck in convincing the other band-members on that approach though