I don't believe the French used more than a can or two of gas.

I don't believe they had more than a few cans of it so far advanced.
But the sauve-qui-peut might have been useless without Feisul's capture, for he was just the man to rally a routed army and snatch victory out of a defeat.

Nobody knew better than Feisul the weakness of the French communications, and the work of those three traitors was only half done when the cavalry took to its heels.

The one man who could possibly save the day had to be bagged and handed over.
I didn't realize all that, of course, in the twinkling of an eye, as they say you do in a climax.

Maybe I've never faced a climax.