The problem is you're basing your argument on a photo of the round's performance in ballistics gel. Actual real-world shootings have shown that, when it comes to actually putting an attacker down, the advantage a .40 has is marginal at best.
The gel is consistant - gives a good baseline comparison.
I think that the photo holds water; the picture on the right matches the numbers on the left.
Marginal at best?
Then why do many police departments use the 40? Its not cause its cheaper, or easier to shoot.
Even if it is just
marginal.. I'll take it.