No you're still wrong, what he meant to say is:
"If you don't, if you get a bunch of D's, you get grain of rice stuck in your ass in Vietnam like I did."
Another flaw in Kerry's "stupid soldier" theory is that you need your best in battle. Combat is "The Most Dangerous Game." You fight smart or die. When we send sad sack screw-ups like Kerry into battle, we put everyone else in the unit at risk.
I, for one, am glad the SOB copped an early out in Nam. If I were in his outfit, I wouldn't want to be looking over my shoulder to see which way he's running.